Sample records for progressive open angle

  1. Myocardial infarction increases progressive visual field defects in well treated early primary open angle glaucoma--a prospective case control study.

    PubMed

    Mondal, Lakshmikanta; Baidya, Krishnapada; Choudhury, Himadri; Roy, Rupam

    2013-06-01

    The purpose of the study was to evaluate the progression of glaucomatous field damage in patients with stable primary open angle glaucoma after an attack of myocardial infarction. In this case control study, 62 open angle glaucoma patients were selected and regularly followed up. Among 62 patients, 9 had an attack of myocardial infarction. The intra-ocular pressure and visual field progression of both the groups (myocardial infarction versus no myocardial infarction) were analysed. Three (33.3%) out of 9 patients who had suffered from myocardial infarction showed progressive visual field loss whereas only 9 (16.9%) out of 53 patients who did not suffer from myocardial infarction, showed progressive field changes. Both the groups had stable target intra-ocular pressure between 14 and 16 mm Hg. Myocardial infarction may adversely influence the progression of primary open angle glaucoma which is suspected to result from ischaemia induced neuronal loss and only control of intraocular pressure is not the only solution. We have to look for other drugs that prevents ischaemia induced neuronal damage.

  2. Biomarkers in primary open angle glaucoma.

    PubMed

    Kokotas, Haris; Kroupis, Christos; Chiras, Dimitrios; Grigoriadou, Maria; Lamnissou, Klea; Petersen, Michael B; Kitsos, George

    2012-12-01

    Glaucoma, a leading cause of blindness worldwide, is currently defined as a disturbance of the structural or functional integrity of the optic nerve that causes characteristic atrophic changes in the optic nerve, which may lead to specific visual field defects over time. This disturbance usually can be arrested or diminished by adequate lowering of intraocular pressure (IOP). Glaucoma can be divided roughly into two main categories, ‘ open angle ’ and ‘ closed angle ’ glaucoma.Open angle, chronic glaucoma tends to progress at a slower rate and patients may not notice loss of vision until the disease has progressed significantly. Primary open angle glaucoma(POAG) is described distinctly as a multifactorial optic neuropathy that is chronic and progressive with a characteristic acquired loss of optic nerve fibers. Such loss develops in the presence of open anterior chamber angles, characteristic visual field abnormalities, and IOP that is too high for the healthy eye. It manifests by cupping and atrophy of the optic disc, in the absence of other known causes of glaucomatous disease. Several biological markers have been implicated with the disease. The purpose of this study was to summarize the current knowledge regarding the non-genetic molecular markers which have been predicted to have an association with POAG but have not yet been validated.

  3. Progressive Decrease of Peripapillary Angioflow Vessel Density During Structural and Visual Field Progression in Early Primary Open-angle Glaucoma.

    PubMed

    Holló, Gábor

    2017-07-01

    To present a case of early primary open-angle glaucoma in which retinal nerve fiber layer thickness (RNFLT), ganglion cell complex (GCC), and visual field progression were accompanied with significant progression of peripapillary angioflow vessel density (PAFD) measured with optical coherence tomographic angiography. A 68-year-old female patient who was under topical intraocular pressure (IOP) lowering medication for 20 years for ocular hypertension of the right and preperimetric primary open-angle glaucoma of the left eye (with reproducible inferotemporal and superotemporal neuroretinal rim and RNFL loss) was prospectively imaged with the AngioVue OCT for RNFLT, GCC thickness, and PAFD, and investigated with the Octopus Normal G2 visual field test on the same days at 6-month intervals for 18 months, while the IOP of the left eye escaped from control. IOP of the left eye fluctuated between 14 and 30 mm Hg in the study period. RNFLT, GCC thickness, and peripapillary PAFD all decreased significantly (linear regression analysis, P=0.030, 0.040, and 0.020, respectively), and a significant 2.1 dB/y progression was seen for a superior visual field cluster. The RNFLT, peripapillary PAFD, and visual field of the right eye remained normal and unchanged. In our case IOP elevation, glaucomatous visual field conversion, and structural progression were accompanied with significant progressive decrease of peripapillary PAFD. The simultaneous thinning of RNFLT and GCC and decrease of peripapillary PAFD suggest that PAFD may potentially be an additional indicator of early progression in primary open-angle glaucoma.

  4. 46 CFR 174.207 - Damaged stability criteria.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... sinkage, heel, and trim, must be below the lower edge of an opening through which progressive flooding may... of this subpart; or (v) Side scuttle of the non-opening type. (2) Angle of heel. The angle of heel...

  5. 46 CFR 172.065 - Damage stability.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of sinkage, heel, and trim, must be below the lower edge of an opening through which progressive... sliding watertight door; or (vi) Side scuttle of the non-opening type. (2) Heel angle. The maximum angle of heel must not exceed 25 degrees, except that this angle may be increased to 30 degrees if no deck...

  6. 46 CFR 172.065 - Damage stability.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of sinkage, heel, and trim, must be below the lower edge of an opening through which progressive... sliding watertight door; or (vi) Side scuttle of the non-opening type. (2) Heel angle. The maximum angle of heel must not exceed 25 degrees, except that this angle may be increased to 30 degrees if no deck...

  7. Long Term Results of Visual Field Progression Analysis in Open Angle Glaucoma Patients Under Treatment.

    PubMed

    Kocatürk, Tolga; Bekmez, Sinan; Katrancı, Merve; Çakmak, Harun; Dayanır, Volkan

    2015-01-01

    To evaluate visual field progression with trend and event analysis in open angle glaucoma patients under treatment. Fifteen year follow-up results of 408 eyes of 217 glaucoma patients who were followed at Adnan Menderes University, Department of Ophthalmology between 1998 and 2013 were analyzed retrospectively. Visual field data were collected for Mean Deviation (MD), Visual Field Index (VFI), and event occurrence. There were 146 primary open-angle glaucoma (POAG), 123 pseudoexfoliative glaucoma (XFG) and 139 normal tension glaucoma (NTG) eyes. MD showed significant change in all diagnostic groups (p<0.001). The difference of VFI between first and last examinations were significantly different in POAG (p<0.001), and XFG (p<0.003) but not in NTG. VFI progression rates were -0.3, -0.43, and -0.2 % loss/year in treated POAG, XFG, and NTG, respectively. The number of empty triangles were statistically different between POAG-NTG (p=0.001), and XFG-NTG (p=0.002) groups. The number of half-filled (p=0.002), and full-filled (p=0.010) triangles were significantly different between XFG-NTG groups. Functional long-term follow-up of glaucoma patients can be monitored with visual field indices. We herein report our fifteen year follow-up results in open angle glaucoma.

  8. 46 CFR 42.20-12 - Conditions of equilibrium.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., heel, and trim, is below the lower edge of any opening through which progressive flooding can take... angle of heel. The angle of heel due to unsymmetrical flooding does not exceed 15 degrees. If no part of the deck is immersed, an angle of heel of up to 17 degrees may be accepted. (d) Metacentric height...

  9. 46 CFR 42.20-12 - Conditions of equilibrium.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., heel, and trim, is below the lower edge of any opening through which progressive flooding can take... angle of heel. The angle of heel due to unsymmetrical flooding does not exceed 15 degrees. If no part of the deck is immersed, an angle of heel of up to 17 degrees may be accepted. (d) Metacentric height...

  10. Perimetric progression using the Visual Field Index and the Advanced Glaucoma Intervention Study score and its clinical correlations.

    PubMed

    Gros-Otero, Juan; Castejón, Miguel; Paz-Moreno, Javier; Mikropoulos, Dimitrios; Teus, Miguel

    2015-01-01

    To evaluate the association between clinical parameters and the diagnosis of progression using VFI (Visual Field Index) and AGIS (Advanced Glaucoma Intervention Study) score in primary open angle glaucoma. Retrospective study of 517 visual fields of 78 eyes with primary open angle glaucoma analyzed with VFI and AGIS score. Clinical data registered included: age, sphere, pachimetry, basal intraocular pressure (IOP), and IOP during the follow up. Only the AGIS score diagnosis of progression was associated with the clinical parameters registered. Among the analyzed data, the mean IOP during follow up (p = 0.0005) and IOP at the third month of follow up (p = 0.004) were statistically associated with progression using the AGIS criteria. The diagnosis of perimetric progression using the AGIS score in the current study was closer to the real functional progression than the diagnosis using the VFI, as the former was associated with known risk factors for progression in glaucoma. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  11. Modifiable factors in the management of glaucoma: a systematic review of current evidence.

    PubMed

    Hecht, Idan; Achiron, Asaf; Man, Vitaly; Burgansky-Eliash, Zvia

    2017-04-01

    Primary open angle glaucoma is a chronic optic neuropathy affecting millions of people worldwide and represents a major public health issue. Environmental factors, behaviors, and diet are intimately related to patient health and may play a role in the pathogenesis and progression of glaucoma. This study aims to review the literature, focusing on the last three years, regarding modifiable lifestyle interventions in the management of primary open angle glaucoma. Electronic databases were searched for studies published between January 2013 and July 2016 on the topic of lifestyle interventions in primary open angle glaucoma. Sleeping with the head elevated and avoiding the worst eye-dependent side during sleep may slightly lower intraocular pressure and reduce visual field loss. Some food supplements and moderate aerobic exercise may also reduce intraocular pressure up to 2.0 and 3.0 mmHg, respectively. Frequency of coffee intake may be associated with disease progression. Potential negative effects are associated with weight-lifting and yoga exercises. Certain lifestyle habits could influence glaucoma progression, yet no specific interventions are currently supported by robust evidence. Awareness of the possible influences of certain habits should help guide clinical advice and is important to help patients avoid adverse outcomes and take an active role in the management of their disease.

  12. Some dissociating factors in the analysis of structural and functional progressive damage in open-angle glaucoma.

    PubMed

    Hudson, C J W; Kim, L S; Hancock, S A; Cunliffe, I A; Wild, J M

    2007-05-01

    To identify the presence, and origin, of any "dissociating factors" inherent to the techniques for evaluating progression that mask the relationship between structural and functional progression in open-angle glaucoma (OAG). 23 patients (14 with OAG and 9 with ocular hypertension (OHT)) who had received serial Heidelberg Retina Tomograph (HRT II) and Humphrey Field Analyser (HFA) examinations for >or=5 years (mean 78.4 months (SD 9.5), range 60-101 months) were identified. Evidence of progressive disease was retrospectively evaluated in one eye of each patient using the Topographic Change Analysis (TCA) and Glaucoma Progression Analysis (GPA) for the HRT II and HFA, respectively. Six patients were stable by both techniques; four exhibited both structural and functional progression; seven exhibited structural progression, only, and six showed functional progression, only. Three types of dissociating factors were identified. TCA failed to identify progressive structural damage in the presence of advanced optic nerve head damage. GPA failed to identify progressive functional damage at stimulus locations, with sensitivities exhibiting test-retest variability beyond the maximum stimulus luminance of the perimeter, and where a perimetric learning effect was apparent. The three dissociating factors accounted for nine of the 13 patients who exhibited a lack of concordance between structural and functional progressive damage.

  13. Progression of visual field in patients with primary open-angle glaucoma - ProgF study 1.

    PubMed

    Aptel, Florent; Aryal-Charles, Nishal; Giraud, Jean-Marie; El Chehab, Hussam; Delbarre, Maxime; Chiquet, Christophe; Romanet, Jean-Paul; Renard, Jean-Paul

    2015-12-01

    To evaluate the visual field rate of progression of patients with treated ocular hypertension (OHT) and primary open-angle glaucoma (POAG) in clinical practice, using the mean deviation (MD) and the visual field index (VFI). Non-interventional cohort study. From a large multicentre database representative of the French population, 441 eyes of 228 patients with treated OHT or POAG followed up at least 6 years with Humphrey 24.2 Sita-Standard visual field examination at least twice a year were identified. From initial data, eyes were classified in five groups: 121 with OHT, 188 with early glaucoma (MD greater than -6 dB), 45 with moderate glaucoma (MD -6 to -12 dB), 41 with advanced glaucoma (MD -12 to -18 dB) and 46 with severe glaucoma (MD less than -18 dB). Rate of progression during the follow-up period was calculated using the trend analysis of the Guided Progression Analysis software. The mean duration of follow-up was 8.4 ± 2.7 years and the mean number of visual field, 18.4 ± 3.5. In eyes with OHT, rate of progression was -0.09 dB/year (-0.17%VFI/year). In eyes with POAG, rate of progression was -0.32 dB/year (-0.83%VFI/year) in eyes with early glaucoma, -0.52 dB/year (-1.81%VFI/year) in moderate glaucoma, -0.54 dB/year (-2.35%VFI/year) in advanced glaucoma and -0.45 dB/year (-1.97%VFI/year) in severe glaucoma. In eyes with POAG, a significant progression (p < 0.05) was detected in 159 of 320 eyes (49.7%) with trend analysis and 117 of 320 eyes (36.6%, likely progression) or 183 of 320 eyes (57.2%, possible and likely progression) with event analysis. Primary open-angle glaucoma is a progressive disease in the majority of patients despite cautioned treatment and follow-up. The rate of progression varies greatly among subjects. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  14. A Small Disc Area Is a Risk Factor for Visual Field Loss Progression in Primary Open-Angle Glaucoma: The Glaucoma Stereo Analysis Study.

    PubMed

    Kitaoka, Yasushi; Tanito, Masaki; Yokoyama, Yu; Nitta, Koji; Katai, Maki; Omodaka, Kazuko; Nakazawa, Toru

    2018-01-01

    The Glaucoma Stereo Analysis Study, a cross-sectional multicenter collaborative study, used a stereo fundus camera (nonmyd WX) to assess various morphological parameters of the optic nerve head (ONH) in glaucoma patients. We compared the associations of each parameter between the visual field loss progression group and no-progression group. The study included 187 eyes of 187 patients with primary open-angle glaucoma or normal-tension glaucoma. We divided the mean deviation (MD) slope values of all patients into the progression group (<-0.3 dB/year) and no-progression group (≧-0.3 dB/year). ONH morphological parameters were calculated with prototype analysis software. The correlations between glaucomatous visual field progression and patient characteristics or each ONH parameter were analyzed with Spearman's rank correlation coefficient. The MD slope averages in the progression group and no-progression group were -0.58 ± 0.28 dB/year and 0.05 ± 0.26 dB/year, respectively. Among disc parameters, vertical disc width (diameter), disc area, cup area, and cup volume in the progression group were significantly less than those in the no-progression group. Logistic regression analysis revealed a significant association between the visual field progression and disc area (odds ratio 0.49/mm 2 disc area). A smaller disc area may be associated with more rapid glaucomatous visual field progression.

  15. [Predicting the probability of development and progression of primary open angle glaucoma by regression modeling].

    PubMed

    Likhvantseva, V G; Sokolov, V A; Levanova, O N; Kovelenova, I V

    2018-01-01

    Prediction of the clinical course of primary open-angle glaucoma (POAG) is one of the main directions in solving the problem of vision loss prevention and stabilization of the pathological process. Simple statistical methods of correlation analysis show the extent of each risk factor's impact, but do not indicate the total impact of these factors in personalized combinations. The relationships between the risk factors is subject to correlation and regression analysis. The regression equation represents the dependence of the mathematical expectation of the resulting sign on the combination of factor signs. To develop a technique for predicting the probability of development and progression of primary open-angle glaucoma based on a personalized combination of risk factors by linear multivariate regression analysis. The study included 66 patients (23 female and 43 male; 132 eyes) with newly diagnosed primary open-angle glaucoma. The control group consisted of 14 patients (8 male and 6 female). Standard ophthalmic examination was supplemented with biochemical study of lacrimal fluid. Concentration of matrix metalloproteinase MMP-2 and MMP-9 in tear fluid in both eyes was determined using 'sandwich' enzyme-linked immunosorbent assay (ELISA) method. The study resulted in the development of regression equations and step-by-step multivariate logistic models that can help calculate the risk of development and progression of POAG. Those models are based on expert evaluation of clinical and instrumental indicators of hydrodynamic disturbances (coefficient of outflow ease - C, volume of intraocular fluid secretion - F, fluctuation of intraocular pressure), as well as personalized morphometric parameters of the retina (central retinal thickness in the macular area) and concentration of MMP-2 and MMP-9 in the tear film. The newly developed regression equations are highly informative and can be a reliable tool for studying of the influence vector and assessment of pathogenic potential of the independent risk factors in specific personalized combinations.

  16. Comparison of optical coherence tomography findings and visual field changes in patients with primary open-angle glaucoma and amyotrophic lateral sclerosis.

    PubMed

    Liu, Ziyuan; Wang, Hongli; Fan, Dongsheng; Wang, Wei

    2018-02-01

    Recent studies revealing genetic connection of primary open angle glaucoma (POAG) and amyotrophic lateral sclerosis (ALS) have received particular attention. Exploring the evidence for common pathogenesis of these two progressive neurological disorders may assist in understanding the mechanism and searching for new treatment. Retinal nerve fiber layer (RNFL) defect and corresponding visual field (VF) impairment are well known neuropathy signs in glaucoma. In our study, thickness of certain retinal layer in ALS patients was analyzed to detect ganglion cell's soma and axon, and for first time visual field was examined for ALS. The correlation of retinal involvement and ALS progression were also investigated. The results were compared with those of POAG. The study may provide new knowledge for these two neurodegenerative diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Risk Factors Associated with Progression to Blindness from Primary Open-Angle Glaucoma in an African-American Population.

    PubMed

    Pleet, Alexander; Sulewski, Melanie; Salowe, Rebecca J; Fertig, Raymond; Salinas, Julia; Rhodes, Allison; Merritt Iii, William; Natesh, Vikas; Huang, Jiayan; Gudiseva, Harini V; Collins, David W; Chavali, Venkata Ramana Murthy; Tapino, Paul; Lehman, Amanda; Regina-Gigiliotti, Meredith; Miller-Ellis, Eydie; Sankar, Prithvi; Ying, Gui-Shuang; O'Brien, Joan M

    2016-08-01

    To determine the risk factors associated with progression to blindness from primary open-angle glaucoma (POAG) in an African-American population. This study examined 2119 patients enrolled in the Primary Open-Angle African-American Glaucoma Genetics (POAAGG) study. A total of 59 eyes were identified as legally blind as a result of POAG (cases) and were age-and sex-matched to 59 non-blind eyes with glaucoma (controls). Chart reviews were performed to record known and suspected risk factors. Cases were diagnosed with POAG at an earlier age than controls (p = 0.005). Of the 59 eyes of cases, 16 eyes (27.1%) presented with blindness at diagnosis. Cases had worse visual acuity (VA) at diagnosis (p < 0.0001), with VA worse than 20/40 conferring a 27 times higher risk of progression to blindness (p = 0.0005). Blind eyes also demonstrated more visual field defects (p = 0.01), higher pre-treatment intraocular pressure (IOP; p < 0.0001), and higher cup-to-disc ratio (p = 0.006) at diagnosis. IOP was less controlled in cases, and those with IOP ≥21 mmHg at more than 20% of follow-up visits were 73 times more likely to become blind (p < 0.0001). Cases missed a greater number of appointments per year (p = 0.003) and had non-adherence issues noted in their charts more often than controls (p = 0.03). However, other compliance data did not significantly differ between groups. Access to care, initial VA worse than 20/40, and poor control of IOP were the major risk factors associated with blindness from POAG. Future studies should examine earlier, more effective approaches to glaucoma screening as well as the role of genetics in these significantly younger patients who progress to blindness.

  18. 33 CFR 157.21 - Subdivision and stability.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... account sinkage, heel, and trim, must be below the lower edge of an opening through which progressive.... (b) In the final stage of flooding, the angle of heel due to unsymmetrical flooding must not exceed...

  19. 33 CFR 157.21 - Subdivision and stability.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... account sinkage, heel, and trim, must be below the lower edge of an opening through which progressive.... (b) In the final stage of flooding, the angle of heel due to unsymmetrical flooding must not exceed...

  20. Relationship between progression of visual field defect and intraocular pressure in primary open-angle glaucoma.

    PubMed

    Naito, Tomoko; Yoshikawa, Keiji; Mizoue, Shiro; Nanno, Mami; Kimura, Tairo; Suzumura, Hirotaka; Shiraga, Fumio

    2015-01-01

    To analyze the relationship between intraocular pressure (IOP) and the progression of visual field defects in Japanese primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG) patients. The subjects of the study were patients undergoing treatment for POAG or NTG who had performed visual field tests at least ten times with a Humphrey field analyzer (Swedish interactive thresholding algorithm standard, C30-2 program). The progression of visual field defects was defined by a significantly negative value of the mean deviation slope at the final visual field test during the follow-up period. The relationships between the progression of visual field defects and IOP, as well as other clinical factors, were retrospectively analyzed. A total of 156 eyes of 156 patients were included in the analysis. Significant progression of visual field defects was observed in 70 eyes of 70 patients (44.9%), while no significant progression was evident in 86 eyes of 86 patients (55.1%). The eyes with visual field defect progression had significantly lower baseline IOP (P<0.05), as well as significantly lower IOP reduction rate (P<0.01). The standard deviation of IOP values during follow-up was significantly greater in the eyes with visual field defect progression than in eyes without (P<0.05). Reducing IOP is thought to be useful for Japanese POAG or NTG patients to suppress the progression of visual field defects. In NTG, IOP management should take into account not only achieving the target IOP, but also minimizing the fluctuation of IOP during follow-up period.

  1. Change in Visual Field Progression Following Treatment Escalation in Primary Open-angle Glaucoma.

    PubMed

    Aptel, Florent; Bron, Alain M; Lachkar, Yves; Schweitzer, Cédric

    2017-10-01

    To evaluate the effect of treatment escalation on the rate of visual field progression in patients with primary open-angle glaucoma (POAG). Multicenter database study. We reviewed the electronic records of 171 patients with POAG under medical hypotensive treatment who underwent 5 consecutive visits 6 months apart before and after medical treatment escalation or additive laser trabeculoplasty. We calculated the rate of visual field progression (mean deviation change per year) before and after treatment escalation. The mean duration of follow-up was 5.1±0.5 years and the mean number of visual field examinations was 10.2±0.2. In 139 eyes with medical treatment escalation, the rate of progression was significantly reduced [from -0.57 to -0.29 dB/y; P=0.022; intraocular pressure (IOP) reduction 11.1%]. In detail, the rate of progression was significantly reduced after escalation from mono to dual therapy, dual to triple therapy, and from mono to triple therapy (-0.35 to -0.24 dB/y, P=0.018; -1.01 to -0.48 dB/y, P=0.038; -1.04 to -0.35 dB/y, P=0.020, respectively). In 32 eyes with additive laser trabeculoplasty, the rate of progression was significantly reduced (-0.60 to -0.24 dB/y; P=0.014; IOP reduction 9.4%). Medical treatment escalation or additive laser trabeculoplasty significantly reduced the rate of visual field progression in POAG. Larger IOP reduction has a greater probability of reducing glaucoma progression.

  2. Risk Factors Associated with Progression to Blindness from Primary Open-Angle Glaucoma in an African-American Population

    PubMed Central

    Pleet, Alexander; Sulewski, Melanie; Salowe, Rebecca J.; Fertig, Raymond; Salinas, Julia; Rhodes, Allison; Merritt, William; Natesh, Vikas; Huang, Jiayan; Gudiseva, Harini V.; Collins, David W.; Chavali, Venkata Ramana Murthy; Tapino, Paul; Lehman, Amanda; Regina-Gigiliotti, Meredith; Miller-Ellis, Eydie; Sankar, Prithvi; Ying, Gui-Shuang; O’Brien, Joan M.

    2016-01-01

    Purpose To determine the risk factors associated with progression to blindness from primary open-angle glaucoma (POAG) in an African-American population. Methods This study examined 2119 patients enrolled in the Primary Open-Angle African-American Glaucoma Genetics (POAAGG) study. A total of 59 eyes were identified as legally blind as a result of POAG (cases) and were age-and sex-matched to 59 non-blind eyes with glaucoma (controls). Chart reviews were performed to record known and suspected risk factors. Results Cases were diagnosed with POAG at an earlier age than controls (p = 0.005). Of the 59 eyes of cases, 16 eyes (27.1%) presented with blindness at diagnosis. Cases had worse visual acuity (VA) at diagnosis (p < 0.0001), with VA worse than 20/40 conferring a 27 times higher risk of progression to blindness (p = 0.0005). Blind eyes also demonstrated more visual field defects (p = 0.01), higher pretreatment intraocular pressure (IOP; p < 0.0001), and higher cup-to-disc ratio (p = 0.006) at diagnosis. IOP was less controlled in cases, and those with IOP ≥21 mmHg at more than 20% of follow-up visits were 73 times more likely to become blind (p < 0.0001). Cases missed a greater number of appointments per year (p = 0.003) and had non-adherence issues noted in their charts more often than controls (p = 0.03). However, other compliance data did not significantly differ between groups. Conclusion Access to care, initial VA worse than 20/40, and poor control of IOP were the major risk factors associated with blindness from POAG. Future studies should examine earlier, more effective approaches to glaucoma screening as well as the role of genetics in these significantly younger patients who progress to blindness. PMID:27348239

  3. Acquired pit of the optic nerve: a risk factor for progression of glaucoma.

    PubMed

    Ugurlu, S; Weitzman, M; Nduaguba, C; Caprioli, J

    1998-04-01

    To examine acquired pit of the optic nerve as a risk factor for progression of glaucoma. In a retrospective longitudinal study, 25 open-angle glaucoma patients with acquired pit of the optic nerve were compared with a group of 24 open-angle glaucoma patients without acquired pit of the optic nerve. The patients were matched for age, mean intraocular pressure, baseline ratio of neuroretinal rim area to disk area, visual field damage, and duration of follow-up. Serial optic disk photographs and visual fields of both groups were evaluated by three independent observers for glaucomatous progression. Of 46 acquired pits of the optic nerve in 37 eyes of 25 patients, 36 pits were located inferiorly (76%) and 11 superiorly (24%; P < .001). Progression of optic disk damage occurred in 16 patients (64%) in the group with acquired pit and in three patients (12.5%) in the group without acquired pit (P < .001). Progression of visual field loss occurred in 14 patients (56%) in the group with acquired pit and in six (25%) in the group without pit (P=.04). Bilateral acquired pit of the optic nerve was present in 12 patients (48%). Disk hemorrhages were observed more frequently in the group with acquired pit (10 eyes, 40%) compared with the group without pit (two eyes, 8%; P=.02). Among patients with glaucoma, patients with acquired pit of the optic nerve represent a subgroup who are at increased risk for progressive optic disk damage and visual field loss.

  4. Investigating the usefulness of a cluster-based trend analysis to detect visual field progression in patients with open-angle glaucoma.

    PubMed

    Aoki, Shuichiro; Murata, Hiroshi; Fujino, Yuri; Matsuura, Masato; Miki, Atsuya; Tanito, Masaki; Mizoue, Shiro; Mori, Kazuhiko; Suzuki, Katsuyoshi; Yamashita, Takehiro; Kashiwagi, Kenji; Hirasawa, Kazunori; Shoji, Nobuyuki; Asaoka, Ryo

    2017-12-01

    To investigate the usefulness of the Octopus (Haag-Streit) EyeSuite's cluster trend analysis in glaucoma. Ten visual fields (VFs) with the Humphrey Field Analyzer (Carl Zeiss Meditec), spanning 7.7 years on average were obtained from 728 eyes of 475 primary open angle glaucoma patients. Mean total deviation (mTD) trend analysis and EyeSuite's cluster trend analysis were performed on various series of VFs (from 1st to 10th: VF1-10 to 6th to 10th: VF6-10). The results of the cluster-based trend analysis, based on different lengths of VF series, were compared against mTD trend analysis. Cluster-based trend analysis and mTD trend analysis results were significantly associated in all clusters and with all lengths of VF series. Between 21.2% and 45.9% (depending on VF series length and location) of clusters were deemed to progress when the mTD trend analysis suggested no progression. On the other hand, 4.8% of eyes were observed to progress using the mTD trend analysis when cluster trend analysis suggested no progression in any two (or more) clusters. Whole field trend analysis can miss local VF progression. Cluster trend analysis appears as robust as mTD trend analysis and useful to assess both sectorial and whole field progression. Cluster-based trend analyses, in particular the definition of two or more progressing cluster, may help clinicians to detect glaucomatous progression in a timelier manner than using a whole field trend analysis, without significantly compromising specificity. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  5. Risk Factors for Primary Open Angle Glaucoma (POAG) Progression: A Study Ruled in Torino

    PubMed Central

    Actis, A.G.; Versino, E.; Brogliatti, B.; Rolle, T.

    2016-01-01

    Purpose: Aim of this retrospective, observational study is to describe features of a population sample, affected by primary open angle glaucoma (POAG) in order to evaluate damage progression on the basis of the emerged individual risk factors. Methods: We included 190 caucasian patients (377 eyes), evaluating relationship between individual risk factors (explicative variables) and MD (Mean Deviation) of standard automated perimetry. We also considered the dependent variable NFI (Neural Fiber Index) of GDx scanning laser polarimetry. Progression has been evaluated through a statistic General Linear Model on four follow up steps (mean follow up 79 months). Results: Factors reaching statistical significance, determining a worsening of the MD variable, are: age (P<0.0001), intraocular pressure (IOP) at follow up (P < 0.0001), female gender (P<0.0001), hypertension (P< 0.0001) and familiarity (P = 0.0006). Factors reaching statistical significance, determining a worsening of the NFI variable, are only IOP at follow up (P = 0.0159) and depression (P = 0.0104). Conclusion: Results of this study confirm and enforce data coming from most recent studies: IOP remains the main risk factor for glaucoma assess and progression; age and familiarity are great risk factors as underlined in the last decades; female sex can be an important risk factors as emerged only in the last years; arterial hypertension should always be evaluated in timing of our clinic follow up. PMID:27347249

  6. Visual field progression in glaucoma: what is the specificity of the Guided Progression Analysis?

    PubMed

    Artes, Paul H; O'Leary, Neil; Nicolela, Marcelo T; Chauhan, Balwantray C; Crabb, David P

    2014-10-01

    To estimate the specificity of the Guided Progression Analysis (GPA) (Carl Zeiss Meditec, Dublin, CA) in individual patients with glaucoma. Observational cohort study. Thirty patients with open-angle glaucoma. In 30 patients with open-angle glaucoma, 1 eye (median mean deviation [MD], -2.5 decibels [dB]; interquartile range, -4.4 to -1.3 dB) was tested 12 times over 3 months (Humphrey Field Analyzer, Carl Zeiss Meditec; SITA Standard, 24-2). "Possible progression" and "likely progression" were determined with the GPA. These analyses were repeated after the order of the tests had been randomly rearranged (1000 unique permutations). Rate of false-positive alerts of "possible progression" and "likely progression" with the GPA. On average, the specificity of the GPA "likely progression" alert was high-for the entire sample, the mean rate of false-positive alerts after 10 follow-up tests was 2.6%. With "possible progression," the specificity was considerably lower (false-positive rate, 18.5%). Most important, the cumulative rate of false-positive alerts varied substantially among patients, from <1% to 80% with "possible progression" and from <0.1% to 20% with "likely progression." Factors associated with false-positive alerts were visual field variability (standard deviation of MD, Spearman's rho = 0.41, P<0.001) and the reliability indices (proportion of false-positive and false-negative responses, fixation losses, rho>0.31, P≤0.10). On average, progression criteria currently used in the GPA have high specificity, but some patients are more likely to show false-positive alerts than others. This is a natural consequence of population-based change criteria and may not matter in clinical trials and studies in which large groups of patients are compared. However, it must be considered when the GPA is used in clinical practice where specificity needs to be controlled for individual patients. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  7. Pathophysiology of primary open-angle glaucoma from a neuroinflammatory and neurotoxicity perspective: a review of the literature.

    PubMed

    Evangelho, Karine; Mogilevskaya, Maria; Losada-Barragan, Monica; Vargas-Sanchez, Jeinny Karina

    2017-12-30

    Glaucoma is the leading cause of blindness in humans, affecting 2% of the population. This disorder can be classified into various types including primary, secondary, glaucoma with angle closure and with open angle. The prevalence of distinct types of glaucoma differs for each particular region of the world. One of the most common types of this disease is primary open-angle glaucoma (POAG), which is a complex inherited disorder characterized by progressive retinal ganglion cell death, optic nerve head excavation and visual field loss. Nowadays, POAG is considered an optic neuropathy, while intraocular pressure is proposed to play a fundamental role in its pathophysiology and especially in optic disk damage. However, the exact mechanism of optic nerve head damage remains a topic of debate. This literature review aims to bring together the information on the pathophysiology of primary open-angle glaucoma, particularly focusing on neuroinflammatory mechanisms leading to the death of the retinal ganglion cell. A literature search was done on PubMed using key words including primary open-angle glaucoma, retinal ganglion cells, Müller cells, glutamate, glial cells, ischemia, hypoxia, exitotoxicity, neuroinflammation, axotomy and neurotrophic factors. The literature was reviewed to collect the information published about the pathophysiologic mechanisms of RGC death in the POAG, from a neuroinflammatory and neurotoxicity perspective. Proposed mechanisms for glaucomatous damage are a result of pressure in RGC followed by ischemia, hypoxia of the ONH, and consequently death due to glutamate-induced excitotoxicity, deprivation of energy and oxygen, increase in levels of inflammatory mediators and alteration of trophic factors flow. These events lead to blockage of anterograde and retrograde axonal transport with ensuing axotomy and eventually blindness. The damage to ganglion cells and eventually glaucomatous injury can occur via various mechanisms including baric trauma, ischemia and impact of metabolic toxins, which triggers an inflammatory process and secondary degeneration in the ONH.

  8. Hierarchical cluster analysis of progression patterns in open-angle glaucoma patients with medical treatment.

    PubMed

    Bae, Hyoung Won; Rho, Seungsoo; Lee, Hye Sun; Lee, Naeun; Hong, Samin; Seong, Gong Je; Sung, Kyung Rim; Kim, Chan Yun

    2014-04-29

    To classify medically treated open-angle glaucoma (OAG) by the pattern of progression using hierarchical cluster analysis, and to determine OAG progression characteristics by comparing clusters. Ninety-five eyes of 95 OAG patients who received medical treatment, and who had undergone visual field (VF) testing at least once per year for 5 or more years. OAG was classified into subgroups using hierarchical cluster analysis based on the following five variables: baseline mean deviation (MD), baseline visual field index (VFI), MD slope, VFI slope, and Glaucoma Progression Analysis (GPA) printout. After that, other parameters were compared between clusters. Two clusters were made after a hierarchical cluster analysis. Cluster 1 showed -4.06 ± 2.43 dB baseline MD, 92.58% ± 6.27% baseline VFI, -0.28 ± 0.38 dB per year MD slope, -0.52% ± 0.81% per year VFI slope, and all "no progression" cases in GPA printout, whereas cluster 2 showed -8.68 ± 3.81 baseline MD, 77.54 ± 12.98 baseline VFI, -0.72 ± 0.55 MD slope, -2.22 ± 1.89 VFI slope, and seven "possible" and four "likely" progression cases in GPA printout. There were no significant differences in age, sex, mean IOP, central corneal thickness, and axial length between clusters. However, cluster 2 included more high-tension glaucoma patients and used a greater number of antiglaucoma eye drops significantly compared with cluster 1. Hierarchical cluster analysis of progression patterns divided OAG into slow and fast progression groups, evidenced by assessing the parameters of glaucomatous progression in VF testing. In the fast progression group, the prevalence of high-tension glaucoma was greater and the number of antiglaucoma medications administered was increased versus the slow progression group. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  9. Risk factors for predicting visual field progression in Chinese patients with primary open-angle glaucoma: A retrospective study.

    PubMed

    Hung, Kuo-Hsuan; Cheng, Ching-Yu; Liu, Catherine Jui-Ling

    2015-07-01

    Glaucoma is a leading cause of irreversible blindness worldwide. It is characterized by progressive deterioration of the visual field (VF) that results in a complete loss of vision. This study aimed to determine the risk factors associated with VF progression in Chinese patients with primary open-angle glaucoma (POAG). We reviewed the charts of POAG patients who visited our clinic between July 2009 and June 2010. We included patients with five or more reliable VF tests using the Humphrey Field Analyzer (Humphrey Instruments, San Leandro, CA, USA) during a period of at least 2 years. The scoring system of the Collaborative Initial Glaucoma Treatment Study (CIGTS) was used to code the VF. Progression was defined as an increasing score ≥3, compared to the averaged baseline data. Univariate and multivariate logistic regression analyses were performed to identify the risk factors of VF progression. There were 92 patients (representing 92 eyes) with an average of 8.9 reliable VFs over a mean follow up of 5.4 years. Multivariate logistic regression showed that eyes with more VF tests [odds ratio (OR) = 1.500, p < 0.010] and either increased peak intraocular pressure (IOP) (OR = 1.235, p = 0.044) or a wide IOP range (OR = 1.165, p = 0.041) favored VF progression. High myopia (less than -6.0 D) was not a risk factor (OR = 1.289, p = 0.698) for VF progression in this study. In addition to a greater number of VF tests, Chinese patients with treated POAG who experienced a high peak IOP or a wide range of IOP during follow up were more likely to have VF deterioration. Copyright © 2015. Published by Elsevier Taiwan.

  10. [A study on residual strain of abdominal aortic aneurysm after intraperitoneal administration of saturated hydrogen saline in rats].

    PubMed

    Song, Yuxiang; Chen, Feng; Xiong, Jiang; Guo, Wei; Pan, Xiujie; Jia, Senhao; Liu, Jie

    2013-07-01

    By observation of the diameter, progression rate, wall thickness, and the opening angle of the abnormal aortic of abdominal aortic aneurysm (AAA) in rats, to observe the effect of saturated hydrogen saline on residual strain of AAA rats, and to investigate its inhibition effect on AAA formation. Twenty healthy male Sprague Dawley rats (weighing, 200-220 g) were randomly divided into 2 groups, which was made the AAA model by infiltration of the abdominal arota with 0.5 mol/L calcium chloride. Saturated hydrogen saline (5 mL/kg) or saline (5 mL/kg) was injected intraperitoneally in the experimental group or control group respectively, every day for 28 days. At 28 days, the diameter, progression rate, wall thickness, and opening angle of the abnormal aorta were mearsured. The aortic tissue was harvested for histological examination (HE staining and aldehyde-fuchsin staining). At 28 days after operation, the diameter of abnormal aorta in 2 groups were significantly higher than preoperative ones (P < 0.05), the progression rate in experimental group (65% +/- 15%) was significantly lower than that in control group (128% +/- 54%) (t=3.611, P=0.005). The opening angle and the wall thickness in experimental group were (88.78 +/- 29.20) degrees and (0.14 +/- 0.03) mm respectively, had significant differences when compared with the values in control group [(44.23 +/- 28.52) degrees and (0.36 +/- 0.05) mm respectively] (P < 0.01). The integrity and continuity of the aortic wall in experimental group were superior to that in the control group. Compared with the control group, the injury of elastic fiber in aortic wall and the infiltration of inflammation were all reduced. Saturated hydrogen saline can maintain good mechanical properties and reduce dilatation of the aorta by increasing residual strain and reducing the remodeling of it.

  11. Glaucoma and clinical characteristics in Vietnamese Americans.

    PubMed

    Peng, Pai-Huei; Manivanh, Richard; Nguyen, Ngoc; Weinreb, Robert N; Lin, Shan C

    2011-08-01

    To assess the proportions of glaucoma types and clinical characteristics in Vietnamese Americans in a single-center, retrospective study. Medical charts of Vietnamese-American patients who visited a single private practice in Northern California from 1998-2007 were reviewed. The main outcome measures included the distribution and characteristics of glaucoma types, and clinical parameters associated with the presence of various glaucomas. Data from 2247 patients aged 18-98 years were reviewed. Glaucoma was determined for 305 patients (13.6%). Among this group, 54.8% had primary open-angle glaucoma (POAG), 26.9% had primary angle-closure glaucoma (PACG), 13.4% had mixed mechanism glaucoma (MMG), and 4.9% had secondary glaucoma. In the MMG group (41 patients), 27 patients who initially had open angles developed narrow angles and underwent laser peripheral iridotomy (LPI) with a mean follow up of 6.4 years from the time of iridotomy. The other 13 patients had glaucoma progression with open angles after LPI. One POAG patient had neovascular glaucoma due to retinal vein occlusion several years later. Compared to the PACG group, the MMG group had significantly lower baseline intraocular pressure (25.0 vs. 20.2 mmHg, p = 0.007) but with no difference in biometry. POAG is the major type of glaucoma in this clinic-based Vietnamese population. However, Vietnamese appear to have a relatively higher proportion of PACG than Caucasians and those of African descent. It is recommended that gonioscopy be part of the regular eye check-up for adult Vietnamese patients.

  12. Relationship between consecutive deterioration of mean deviation value and progression of visual field defect in open-angle glaucoma.

    PubMed

    Naito, Tomoko; Yoshikawa, Keiji; Mizoue, Shiro; Nanno, Mami; Kimura, Tairo; Suzumura, Hirotaka; Takeda, Ryuji; Shiraga, Fumio

    2015-01-01

    To analyze the relationship between consecutive deterioration of mean deviation (MD) value and glaucomatous visual field (VF) progression in open-angle glaucoma (OAG), including primary OAG and normal tension glaucoma. The subjects of the study were patients undergoing treatment for OAG who had performed VF tests at least 10 times with a Humphrey field analyzer (SITA standard, C30-2 program). The VF progression was defined by a significantly negative MD slope (MD slope worsening) at the final VF test during the follow-up period. The relationship between the MD slope worsening and the consecutive deterioration of MD value were retrospectively analyzed. A total of 165 eyes of 165 patients were included in the analysis. Significant progression of VF defects was observed in 72 eyes of 72 patients (43.6%), while no significant progression was evident in 93 eyes of 93 patients (56.4%). There was significant relationship between the frequency of consecutive deterioration of MD value and MD slope worsening (P<0.0001, Cochran-Armitage trend test). A significant association was observed for MD slope worsening in the eyes with three (odds ratio: 2.1, P=0.0224) and four (odds ratio: 3.6, P=0.0008) consecutive deterioration of MD value in multiple logistic regression analysis, but no significant association in the eyes with two consecutive deterioration (odds ratio: 1.1, P=0.8282). The eyes with VF progression had significantly lower intraocular pressure reduction rate (P<0.01). This retrospective study has shown that three or more consecutive deterioration of MD value might be a predictor to future significant MD slope worsening in OAG.

  13. Glaucoma

    MedlinePlus

    Open-angle glaucoma; Chronic glaucoma; Chronic open-angle glaucoma; Primary open-angle glaucoma; Closed-angle glaucoma; Narrow-angle glaucoma; Angle-closure glaucoma; Acute glaucoma; Secondary glaucoma; Congenital glaucoma; Vision ...

  14. Mitral Valve Stenosis after Open Repair Surgery for Non-rheumatic Mitral Valve Regurgitation: A Review.

    PubMed

    Shabsigh, Muhammad; Lawrence, Cassidy; Rosero-Britton, Byron R; Kumar, Nicolas; Kimura, Satoshi; Durda, Michael Andrew; Essandoh, Michael

    2016-01-01

    Mitral stenosis (MS) after mitral valve (MV) repair is a slowly progressive condition, usually detected many years after the index MV surgery. It is defined as a mean transmitral pressure gradient (TMPG) >5 mmHg or a mitral valve area (MVA) <1.5 cm(2). Pannus formation around the mitral annulus or extending to the mitral leaflets is suggested as the main mechanism for developing delayed MS after MV repair. On the other hand, early stenosis is thought to be a direct result of an undersized annuloplasty ring. Furthermore, in MS following ischemic mitral regurgitation (MR) repair, subvalvular tethering is the hypothesized pathophysiology. MS after MV repair has an incidence of 9-54%. Several factors have been associated with a higher risk for developing MS after MV repair, including the use of flexible Duran annuloplasty rings versus rigid Carpentier-Edwards rings, complete annuloplasty rings versus partial bands, small versus large anterior leaflet opening angle, and anterior leaflet tip opening length. Intraoperative echocardiography can measure the anterior leaflet opening angle, the anterior leaflet tip opening dimension, the MVA and the mean TMPG, and may help identify patients at risk for developing MS after MV repair.

  15. Mitral Valve Stenosis after Open Repair Surgery for Non-rheumatic Mitral Valve Regurgitation: A Review

    PubMed Central

    Shabsigh, Muhammad; Lawrence, Cassidy; Rosero-Britton, Byron R.; Kumar, Nicolas; Kimura, Satoshi; Durda, Michael Andrew; Essandoh, Michael

    2016-01-01

    Mitral stenosis (MS) after mitral valve (MV) repair is a slowly progressive condition, usually detected many years after the index MV surgery. It is defined as a mean transmitral pressure gradient (TMPG) >5 mmHg or a mitral valve area (MVA) <1.5 cm2. Pannus formation around the mitral annulus or extending to the mitral leaflets is suggested as the main mechanism for developing delayed MS after MV repair. On the other hand, early stenosis is thought to be a direct result of an undersized annuloplasty ring. Furthermore, in MS following ischemic mitral regurgitation (MR) repair, subvalvular tethering is the hypothesized pathophysiology. MS after MV repair has an incidence of 9–54%. Several factors have been associated with a higher risk for developing MS after MV repair, including the use of flexible Duran annuloplasty rings versus rigid Carpentier–Edwards rings, complete annuloplasty rings versus partial bands, small versus large anterior leaflet opening angle, and anterior leaflet tip opening length. Intraoperative echocardiography can measure the anterior leaflet opening angle, the anterior leaflet tip opening dimension, the MVA and the mean TMPG, and may help identify patients at risk for developing MS after MV repair. PMID:27148540

  16. Rate of progression of total, upper, and lower visual field defects in patients with open-angle glaucoma and high myopia.

    PubMed

    Yoshino, Takaiko; Fukuchi, Takeo; Togano, Tetsuya; Sakaue, Yuta; Seki, Masaaki; Tanaka, Takayuki; Ueda, Jun

    2016-03-01

    We evaluated the rate of progression of total, upper, and lower visual field defects in patients with treated primary open-angle glaucoma (POAG) with high myopia (HM). Seventy eyes of 70 POAG patients with HM [≤-8 diopters (D)] were examined. The mean deviation (MD) slope and the upper and lower total deviation (upper TD, lower TD) slopes of the Humphrey Field Analyzer were calculated in patients with high-tension glaucoma (HTG) (>21 mmHg) versus normal-tension glaucoma (NTG) (≤21 mmHg). The mean age of all the patients (29 eyes with HTG and 41 eyes with NTG) was 48.5 ± 9.6 years. The MD slope, and upper and lower TD slopes of the HM group were compared to those of the non-HM group (NHM) (>-8 D) selected from 544 eyes in 325 age-matched POAG patients. In all, 70 eyes with HM and NHM were examined. The mean MD slope was -0.33 ± 0.33 dB/year in the HM, and -0.38 ± 0.49 dB/year in the NHM. There were no statistical differences between the HM and NHM (p = 0.9565). In the comparison of HTG versus NTG patients in both groups, the MD slope, and upper and lower TD slopes were similar. The rate of progression of total, upper, and lower visual field defects was similar among patients with HM and NHM. Although HM is a risk factor for the onset of glaucoma, HM may not be a risk factor for progression of visual field defects as assessed by the progression rate under treatment.

  17. Angle closure glaucoma in congenital ectropion uvea.

    PubMed

    Wang, Grace M; Thuente, Daniel; Bohnsack, Brenda L

    2018-06-01

    Congenital ectropion uvea is a rare anomaly, which is associated with open, but dysplastic iridocorneal angles that cause childhood glaucoma. Herein, we present 3 cases of angle-closure glaucoma in children with congenital ectropion uvea. Three children were initially diagnosed with unilateral glaucoma secondary to congenital ectropion uvea at 7, 8 and 13 years of age. The three cases showed 360° of ectropion uvea and iris stromal atrophy in the affected eye. In one case, we have photographic documentation of progression to complete angle closure, which necessitated placement of a glaucoma drainage device 3 years after combined trabeculotomy and trabeculectomy. The 2 other cases, which presented as complete angle closure, also underwent glaucoma drainage device implantation. All three cases had early glaucoma drainage device encapsulation (within 4 months) and required additional surgery (cycloablation or trabeculectomy). Congenital ectropion uvea can be associated with angle-closure glaucoma, and placement of glaucoma drainage devices in all 3 of our cases showed early failure due to plate encapsulation. Glaucoma in congenital ectropion uvea requires attention to angle configuration and often requires multiple surgeries to obtain intraocular pressure control.

  18. Crack Coalescence in Molded Gypsum and Carrara Marble

    NASA Astrophysics Data System (ADS)

    Wong, N.; Einstein, H. H.

    2007-12-01

    This research investigates the fracturing and coalescence behavior in prismatic laboratory-molded gypsum and Carrara marble specimens, which consist of either one or two pre-existing open flaws, under uniaxial compression. The tests are monitored by a high speed video system with a frame rate up to 24,000 frames/second. It allows one to precisely observe the cracking mechanisms, in particular if shear or tensile fracturing takes place. Seven crack types and nine crack coalescence categories are identified. The flaw inclination angle, the ligament length and the bridging angle between two flaws have different extents of influence on the coalescence patterns. For coplanar flaws, as the flaw inclination angle increases, there is a general trend of variation from shear coalescence to tensile coalescence. For stepped flaws, as the bridging angle changes from negative to small positive, and further up to large positive values, the coalescence generally progresses from categories of no coalescence, indirect coalescence to direct coalescence. For direct coalescence, it generally progresses from shear, mixed shear-tensile to tensile as the bridging angle increases. Some differences in fracturing and coalescence processes are observed in gypsum and marble, particularly the crack initiation in marble is preceded by the development of macroscopic white patches, but not in gypsum. Scanning Electron Microprobe (SEM) study reveals that the white patches consist of zones of microcracks (process zones).

  19. Axial Myopia Is Associated with Visual Field Prognosis of Primary Open-Angle Glaucoma

    PubMed Central

    Qiu, Chen; Qian, Shaohong; Sun, Xinghuai; Zhou, Chuandi; Meng, Fanrong

    2015-01-01

    Purpose To identify whether myopia was associated with the visual field (VF) progression of primary open-angle glaucoma (POAG). Methods A total of 270 eyes of 270 POAG followed up for more than 3 years with ≥9 reliable VFs by Octopus perimetry were retrospectively reviewed. Myopia was divided into: mild myopia (-2.99 diopter [D], 0), moderate myopia (-5.99, 3.00 D), marked myopia (-9.00, -6.00 D) and non-myopia (0 D or more). An annual change in the mean defect (MD) slope >0.22 dB/y and 0.30 dB/y was defined as fast progression, respectively. Logistic regression was performed to determine prognostic factors for VF progression. Results For the cutoff threshold at 0.22 dB/y, logistic regression showed that vertical cup-to-disk ratio (VCDR; p = 0.004) and the extent of myopia (p = 0.002) were statistically significant. When logistic regression was repeated after excluding the extent of myopia, axial length (AL; p = 0.008, odds ratio [OR] = 0.796) reached significance, as did VCDR (p = 0.001). Compared to eyes with AL≤23 mm, the OR values were 0.334 (p = 0.059), 0.309 (p = 0.044), 0.266 (p = 0.019), 0.260 (p = 0.018), respectively, for 23 26 mm. The significance of vertical cup-to-disk ratio of (p = 0.004) and the extent of myopia (p = 0.008) did not change for the cutoff threshold at 0.30dB/y. Conclusions VCDR and myopia were associated with VF prognosis of POAG. Axial myopia may be a protective factor against VF progression. PMID:26214313

  20. [Basic and clinical studies of pressure-independent damaging factors of open angle glaucoma].

    PubMed

    Araie, Makoto

    2011-03-01

    Pathogenesis of open-angle glaucoma involves both pressure-dependent damaging factors and pressure-independent damaging factors. The high prevalence of open-angle glaucoma with normal pressure (normal-tension glaucoma) in Japan implies that treatment of pressure-independent damaging factors in Japanese open-angle glaucoma patients is of importance. In an attempt to investigate the roles of pressure-independent damaging factors in open-angle glaucoma, we carried out basic and clinical studies and obtained the following results. 1. The rate of deterioration of visual field after trabeculectomy in normal tension glaucoma patients with post-operative intraocular pressure (IOP) of 10 mmHg was found to be -0.25 dB/year of mean deviation (MD), suggesting that contribution of pressure-independent damaging factors to the deterioration of MD in open-angle glaucoma is around -0.25 dB/year of mean deviation (MD). 2. Experiments using isolated purified cultured retinal ganglion cells (RGCs) indicated that calcium-channel blockers and some of antiglaucoma drugs showed neuroprotective effects on RGCs at concentrations of 0.01 microM or higher. 3. In mice, damage to RGCs resulted in secondary degeneration of neurons and activation of glial cells in the lateral geniculate nucleous (LGN) and superior colliculus, and these secondary changes in the central nervous system (CNS) due to RGC damage was partly ameliorated by systemic administration of memantine. 4. Mice experimental high IOP glaucoma models could be established using laser irradiation of the limbal area, and the usefulness of Tonolab in IOP measurements of mice eye was confirmed. 5. Monkey experimental high IOP glaucoma models revealed that in the glaucomatous optic nerve head vaso-constrictive reactions to an alpha-1 agonist was abolished, while vasodilative reaction to a prostaglandin FP receptor agonist was retained. 6. In monkeys with experimental high IOP glaucoma, secondary damage to neurons in the LGN and the glial reaction to it were also found, similar to the mice experiments. In living monkeys the glial reaction in the LGN could be observed by means of positron emission tomography. 7. In the LGN of monkeys with experimental high IOP glaucoma, the M-cell system was preferentially damaged in the early stage, while in the later stages both the M- and P-cell systems were damaged. 8. In a single-instituted prospective double-blinded clinical trial, oral administration of nilvadipine at 4 mg/day, a DHP calcium-channel blocker, was found to significantly retard the visual field progression in normal tension glaucoma patients over 3 years, while significantly increasing the choroidal and optic nerve blood flow by about 35%. 9. A multi-instituted prospective double-blinded clinical trial in normal tension glaucoma patients revealed that the rate of MD deterioration under monotherapy with either topical nipradilol or timolol was around -0.05 dB/year, thought to be considerably slower than -0.25 dB/year, the commonly estimated rate of MD deterioration by pressure-independent damaging factors. The current results indicate the possibility of treatment of pressure-independent damaging factors of open-angle glaucoma in Japanese open-angle glaucoma patients with oral nilvadipine and topical anti-glaucoma agents.

  1. Evaluation of blotchy pigments in the anterior chamber angle as a sign of angle closure

    PubMed Central

    Rao, Harsha L; Mungale, Sachin C; Kumbar, Tukaram; Parikh, Rajul S; Garudadri, Chandra S

    2012-01-01

    Background: Blotchy pigments in the anterior chamber (AC) angle are considered diagnostic of primary angle closure (PAC). But there are no reports either on the prevalence of blotchy pigments in AC angles or the validity of this sign. Aims: To determine the prevalence of blotchy pigments in AC angles and to evaluate their relationship with glaucomatous optic neuropathy (GON) in eyes with occludable angles. Setting and Design: Cross-sectional, comparative study. Materials and Methods: Gonioscopy was performed in 1001 eyes of 526 subjects (245 eyes of 148 consecutive, occludable angle subjects and 756 eyes of 378 non-consecutive, open angle subjects), above 35 years of age. Quadrant-wise location of blotchy pigments was documented. Statistical Analysis: Odds of blotchy pigments in occludable angles against that in open angles were evaluated. Relationship of GON with blotchy pigments in occludable angle eyes was evaluated using a multivariate model. Results: Prevalence of blotchy pigments in occludable angles was 28.6% (95% CI, 22.9-34.3) and in open angles was 4.7% (95% CI, 3.2-6.3). Blotchy pigments were more frequently seen in inferior (16%) and superior quadrants (15%) of occludable angles, and inferior quadrant of open angles (4%). Odds of superior quadrant blotchy pigments in occludable angles were 33 times that in open angles. GON was seen in 107 occludable angle eyes. Blotchy pigments were not significantly associated with GON (odds ratio = 0.5; P = 0.1). Conclusions: Blotchy pigments were seen in 28.6% of occludable angle eyes and 4.7% of open angles eyes. Presence of blotchy pigments in the superior quadrant is more common in occludable angles. Presence of GON in occludable angle eyes was not associated with blotchy pigments. PMID:23202393

  2. Preserve the (intraocular) environment: the importance of maintaining normal oxygen gradients in the eye.

    PubMed

    Beebe, David C; Shui, Ying-Bo; Siegfried, Carla J; Holekamp, Nancy M; Bai, Fang

    2014-05-01

    Oxygen levels in the eye are generally low and tightly regulated. Oxygen enters the eye largely by diffusion from retinal arterioles and through the cornea. In intact eyes, oxygen from the retinal arterioles diffuses into the vitreous body. There is a decreasing oxygen gradient from the retina to the lens, established by oxygen consumption by ascorbate in the vitreous fluid and lens metabolism. Age-related degeneration of the vitreous body or removal during vitrectomy exposes the posterior of the lens to increased oxygen, causing nuclear sclerotic cataracts. Lowering oxygen in the vitreous, as occurs in patients with ischemic diabetic retinopathy, protects against cataracts after vitrectomy. Vitrectomy and cataract surgery increase oxygen levels at the trabecular meshwork and with it the risk of open angle glaucoma. Two additional risk factors for glaucoma, African heritage and having a thinner cornea, are also associated with increased oxygen in the anterior chamber angle. Preservation of the vitreous body and the lens, two important oxygen consumers, would protect against nuclear sclerotic cataracts and open angle glaucoma. Delaying removal of the lens for as long as possible after vitrectomy would be an important step in delaying ocular hypertension and glaucoma progression.

  3. Reducing the visual burden of glaucoma in Asia: what we know and what we need to know.

    PubMed

    Congdon, Nathan

    2009-01-01

    Despite great progress in elucidating risk factors and effective treatments for eye disease in the last decades, blindness prevalence in the developing and developed world is either static or rising. A research agenda is needed to develop and test specific strategies to reduce the burden of blindness from glaucoma and other common eye diseases. Current knowledge about open and closed-angle glaucoma is reviewed and a strategy to reduce glaucoma blindness in Asia is suggested. A critical component of this strategy is enhanced training in the detection of narrow angles and optic nerve damage by direct examination. Specific research topics that could inform such a strategy are outlined.

  4. Wetting Hysteresis at the Molecular Scale

    NASA Technical Reports Server (NTRS)

    Jin, Wei; Koplik, Joel; Banavar, Jayanth R.

    1996-01-01

    The motion of a fluid-fluid-solid contact line on a rough surface is well known to display hysteresis in the contact angle vs. velocity relationship. In order to understand the phenomenon at a fundamental microscopic level, we have conducted molecular dynamics computer simulations of a Wilhelmy plate experiment in which a solid surface is dipped into a liquid bath, and the force-velocity characteristics are measured. We directly observe a systematic variation of force and contact angle with velocity, which is single-valued for the case of an atomically smooth solid surface. In the microscopically rough case, however, we find (as intuitively expected) an open hysteresis loop. Further characterization of the interface dynamics is in progress.

  5. Is high myopia a risk factor for visual field progression or disk hemorrhage in primary open-angle glaucoma?

    PubMed

    Nitta, Koji; Sugiyama, Kazuhisa; Wajima, Ryotaro; Tachibana, Gaku

    2017-01-01

    The purpose of this study was to clarify differences between highly myopic and non-myopic primary open-angle glaucoma (POAG) patients, including normal-tension glaucoma patients. A total of 269 POAG patients were divided into two groups: patients with ≥26.5 mm of axial length (highly myopic group) and patients with <24.0 mm of axial length (non-myopic group). We analyzed 53 highly myopic and 93 non-myopic POAG patients. Age at first visit of the highly myopic group was significantly less than that of the non-myopic group ( P <0.0001). Baseline intraocular pressures (IOPs) showed no significant differences. Follow-up IOPs of the non-myopic group were significantly lower than those of the highly myopic group ( P =0.0009). According to the mean deviation definition of progression, the cumulative probability of non-progression of visual field (VF) loss was significantly greater in the highly myopic group (10-year survival rate, 73.7%±6.8%) than in the non-myopic group (10-year survival rate, 46.3%±5.8%; log-rank test, P =0.0142). The occurrence of disk hemorrhage (DH) in the non-myopic group (1.60±3.04) was significantly greater than that in the highly myopic group (0.93±2.13, P =0.0311). The cumulative probability of DH was significantly lower in the highly myopic group (10-year survival rate, 26.4%±5.4%) than in the non-myopic group (10-year survival rate, 47.2%±6.6%, P =0.0413). Highly myopic POAG is considered as a combination of myopic optic neuropathy and glaucomatous optic neuropathy (GON). If GON is predominant, it has frequent DH and more progressive VF loss. However, when the myopic optic neuropathy is predominant, it has less DH and less progressive VF loss.

  6. Glaucoma: Symptoms and Causes

    MedlinePlus

    ... damage. The types of glaucoma include the following: Open-angle glaucoma Open-angle glaucoma is the most common form of ... angle formed by the cornea and iris remains open, but the trabecular meshwork is partially blocked. This ...

  7. Using filtered forecasting techniques to determine personalized monitoring schedules for patients with open-angle glaucoma.

    PubMed

    Schell, Greggory J; Lavieri, Mariel S; Helm, Jonathan E; Liu, Xiang; Musch, David C; Van Oyen, Mark P; Stein, Joshua D

    2014-08-01

    To determine whether dynamic and personalized schedules of visual field (VF) testing and intraocular pressure (IOP) measurements result in an improvement in disease progression detection compared with fixed interval schedules for performing these tests when evaluating patients with open-angle glaucoma (OAG). Secondary analyses using longitudinal data from 2 randomized controlled trials. A total of 571 participants from the Advanced Glaucoma Intervention Study (AGIS) and the Collaborative Initial Glaucoma Treatment Study (CIGTS). Perimetric and tonometric data were obtained for AGIS and CIGTS trial participants and used to parameterize and validate a Kalman filter model. The Kalman filter updates knowledge about each participant's disease dynamics as additional VF tests and IOP measurements are obtained. After incorporating the most recent VF and IOP measurements, the model forecasts each participant's disease dynamics into the future and characterizes the forecasting error. To determine personalized schedules for future VF tests and IOP measurements, we developed an algorithm by combining the Kalman filter for state estimation with the predictive power of logistic regression to identify OAG progression. The algorithm was compared with 1-, 1.5-, and 2-year fixed interval schedules of obtaining VF and IOP measurements. Length of diagnostic delay in detecting OAG progression, efficiency of detecting progression, and number of VF and IOP measurements needed to assess for progression. Participants were followed in the AGIS and CIGTS trials for a mean (standard deviation) of 6.5 (2.8) years. Our forecasting model achieved a 29% increased efficiency in identifying OAG progression (P<0.0001) and detected OAG progression 57% sooner (reduced diagnostic delay) (P = 0.02) than following a fixed yearly monitoring schedule, without increasing the number of VF tests and IOP measurements required. The model performed well for patients with mild and advanced disease. The model performed significantly more testing of patients who exhibited OAG progression than nonprogressing patients (1.3 vs. 1.0 tests per year; P<0.0001). Use of dynamic and personalized testing schedules can enhance the efficiency of OAG progression detection and reduce diagnostic delay compared with yearly fixed monitoring intervals. If further validation studies confirm these findings, such algorithms may be able to greatly enhance OAG management. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  8. Open-angle glaucoma in patients with diabetic retinopathy at the Puerto Rico Medical Center.

    PubMed

    Cruz-lñigo, Yousef; Izquierdo, Natalio J; García, Omar; Pérez, Raúl

    2012-01-01

    The association of open-angle glaucoma (OAG) with diabetes mellitus remains controversial. We report on the frequency of open-angle glaucoma in patients having diabetic retinopathy in a population of the Puerto Rico Medical Center. A cross-sectional study of 1,442 patients was done. Only the chart of patients 40 years-of-age and older, with a diagnosis of diabetic retinopathy and/or open-angle glaucoma were included. Descriptive analysis was done. Unadjusted and gender-adjusted logistic regression analyses were used to estimate risk of developing open-angle glaucoma in patients with diabetic retinopathy for each subsequent decade. 1,040 patients were diagnosed with diabetic retinopathy from July 1, 2004 to June 30, 2009. Also, 402 patients were diagnosed with open-angle glaucoma from July 1, 2007 to June 30, 2009. Of the 1,040 patients with diabetic retinopathy, 64 patients (6.15%) also had OAG. According to our gender-adjusted logistic regression analysis the estimated risk of developing open-angle glaucoma for patients 40 years-of-age with diabetic retinopathy increased for each subsequent decade until the seventh decade, odds ratio = 5.07 (95% confidence interval: 1.62-15.86). Thereafter, it decreased, odds ratio = 2.07 (95% confidence interval: 0.36-11.82). Our findings suggest that Puerto Rico patients between 40 to 79 years of age with diabetic retinopathy have an increased risk of developing open-angle glaucoma with each subsequent decade. Screening for open-angle glaucoma in patients with diabetic retinopathy is of utmost importance in the aging Puerto Rico population to prevent blindness.

  9. A Genetic Variant in TGFBR3-CDC7 Is Associated with Visual Field Progression in Primary Open-Angle Glaucoma Patients from Singapore.

    PubMed

    Trikha, Sameer; Saffari, Ehsan; Nongpiur, Monisha; Baskaran, Mani; Ho, Henrietta; Li, Zheng; Tan, Peng-Yi; Allen, John; Khor, Chiea-Chuen; Perera, Shamira A; Cheng, Ching-Yu; Aung, Tin; Vithana, Eranga

    2015-12-01

    To investigate whether known genetic loci for primary open-angle glaucoma (POAG) are associated with visual field (VF) progression in patients from a Singaporean Chinese population. Retrospective study. Patients with 5 or more reliable VF measurements who were being followed up at a Singapore hospital. Visual field progression was identified using Progressor software version 3.7 (Medisoft, Leeds, United Kingdom) and defined by pointwise linear regression (PLR) criteria as follows: any 2 contiguous points in the same hemifield progressing (≤-1.00 dB/year for inner points and ≤-2.00 dB/year for edge points; P < 0.01). Single nucleotide polymorphisms (SNPs) and their proxies from 10 POAG-associated loci (CAV1-CAV2, CDKN2B-AS1, SIX1-SIX6, an intergenic region on chromosome 8q22, ABCA1, GAS7, AFAP1, GMDS, PMM2, and TGFBR3-CDC7) identified from genome-wide association studies were tested for association with VF progression using logistic regression with an additive genetic model adjusting for age, gender, average intraocular pressure (IOP), central corneal thickness (CCT), and baseline vertical cup-to-disc ratio (VCDR). Visual field progression. Of the 1334 patients included in the study, 469 subjects (35.1%) completed 5 or more reliable VF measurements (mean follow-up, 9.01 years; standard deviation, 5.00 years). The mean age of patients was 59.6 years (standard deviation, 9.0 years); 305 patients were men and all were Chinese. The average IOP in eyes fulfilling PLR progression was 16.5 mmHg versus 17.7 mmHg in those who did not (P = 0.52). Univariate analysis revealed that increased VCDR (P = 0.003), reduced CCT (P = 0.045), and reduced superior and inferior retinal nerve fiber layer thickness (P = 0.01, respectively) were associated with VF progression. No clinical or structural features were associated significantly with VF progression on multivariate analysis. The rs1192415 index SNP in TGFBR3-CDC7 (P = 0.002; odds ratio, 6.71 per risk allele) was the only SNP associated with VF progression. The presence of the index SNP rs1192415 (TGFBR3-CDC7) was associated with VF progression in POAG patients. These findings warrant further investigation in independent cohorts. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  10. Comparison between Closing-Wedge and Opening-Wedge High Tibial Osteotomy in Patients with Medial Knee Osteoarthritis: A Systematic Review and Meta-analysis.

    PubMed

    Sun, Hao; Zhou, Lin; Li, Fengsheng; Duan, Jun

    2017-02-01

    Young active patients with medial knee osteoarthritis (OA) combined with varus leg alignment can be treated with high tibial osteotomy (HTO) to stop the progression of OA and avoid or postpone total knee arthroplasty (TKA). Closing-wedge osteotomy (CWO) and opening-wedge osteotomy (OWO) are the most commonly used osteotomy techniques. The purpose of this study was to compare the clinical and radiologic outcomes and complications between OWO and CWO. We retrospectively evaluated 23 studies including 17 clinical trials from published databases from their inception to May 2015. We evaluated the clinical outcomes including operation time, visual analog scale (VAS), maximal flexion, and hospital for special surgery knee (HSS) score. The radiologic outcomes included patellar height measured by posterior tibial slope angle, hip-knee-ankle (HKA) angle, femorotibial (FT) axis, and limb length. Complications recorded included the incidence of deep vein thrombosis (DVT), common peroneal nerve injury, opposite cortical fracture, etc. There were no differences in most of the clinical outcomes except the operation time. OWO increased the posterior slope angle and limb length, decreased the patellar height, and provided higher accuracy of correction. CWO led to a higher incidence of opposite cortical fracture. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  11. Assessment of Retinal Nerve Fiber Layer Using Optical Coherence Tomography and Scanning Laser Polarimetry in Progressive Glaucomatous Optic Neuropathy

    PubMed Central

    Sehi, Mitra; Greenfield, David S.

    2006-01-01

    Purpose To describe a case of progressive glaucomatous optic neuropathy using scanning laser polarimetry with fixed (SLP-FCC) and variable corneal compensation (SLP-VCC) and optical coherence tomography (OCT). Design Observational case report. Methods A 21-year-old male with juvenile primary open-angle glaucoma developed progression because of noncompliance with therapy. The patient underwent dilated stereoscopic examination and photography of the optic disk, standard automated perimetry (SAP), OCT, and SLP imaging with FCC and VCC at the baseline examination and after four years of follow-up. Results Optic disk, retinal nerve fiber layer (RNFL) atrophy, and SAP progression was observed. Reduction in mean RNFL thickness (average, superior, inferior) was 18, 18, and 27 microns (OCT); 22, 40, and 17 microns (SLP-FCC); and 6, 12, and 12 microns (SLP-VCC), respectively. Conclusions This case demonstrates that digital imaging of the peripapillary RNFL is capable of documentation and measurement of progressive glaucomatous RNFL atrophy. PMID:17157591

  12. Evaluation of the anterior chamber angle in Asian Indian eyes by ultrasound biomicroscopy and gonioscopy.

    PubMed

    Kaushik, Sushmita; Jain, Rajeev; Pandav, Surinder Singh; Gupta, Amod

    2006-09-01

    To compare the ultrasound biomicroscopic measurement of the anterior chamber angle in Asian Indian eyes, with the angle width estimated by gonioscopy. Patients with open and closed angles attending a glaucoma clinic were recruited for the study. Temporal quadrants of the angles of patients were categorized by gonioscopy as Grade 0 to Grade 4, using Shaffer's classification. These angles were quantified by ultrasound biomicroscopy (UBM) using the following biometric characteristics: Angle opening distance at 250 micro (AOD 250) and 500 micro (AOD 500) from the scleral spur and trabecular meshwork-ciliary process distance (TCPD). The angles were further segregated as "narrow angles" (Schaffer's Grade 2 or less) and "open angles" (Schaffer's Grade 3 and 4). The UBM measurements were computed in each case and analyzed in relation to the gonioscopic angle evaluation. One hundred and sixty three eyes of 163 patients were analyzed. One hundred and six eyes had "narrow angles" and 57 eyes had "open angles" on gonioscopy. There was a significant difference among the mean UBM measurements of each angle grade estimated by gonioscopy (P < 0.001). The Pearson correlation coefficient between all UBM parameters and gonioscopy grades was significant at the 0.01 level. The mean AOD 250, AOD 500 and TCPD in narrow angles were 58+/-49 micro, 102+/-84 micro and 653+/-124 respectively, while it was 176+/-47 micro, 291+/-62 micro and 883+/-94 micro in eyes with open angles (P < 0.001) respectively. The angle width estimated by gonioscopy correlated significantly with the angle dimensions measured by UBM. Gonioscopy, though a subjective test, is a reliable method for estimation of the angle width.

  13. Lamina cribrosa position and Bruch's membrane opening differences between anterior ischemic optic neuropathy and open-angle glaucoma.

    PubMed

    Rebolleda, Gema; Pérez-Sarriegui, Ane; Díez-Álvarez, Laura; De Juan, Victoria; Muñoz-Negrete, Francisco J

    2018-06-01

    To compare the optic nerve head morphology among primary open-angle glaucoma, non-arteritic anterior ischemic optic neuropathy eyes, their fellow healthy eyes and control eyes, using spectral-domain optical coherence tomography with enhanced depth imaging. Observational cross-sectional study including 88 eyes of 68 patients. In this study, 23 non-arteritic anterior ischemic optic neuropathy eyes, 17 fellow unaffected eyes, 25 primary open-angle glaucoma eyes, and 23 age-matched control eyes were included. Peripapillary retinal nerve fiber layer thickness and optic disk area were evaluated. Bruch's membrane opening diameter, optic cup depth, anterior lamina cribrosa depth, and prelaminar tissue thickness were assessed. Non-arteritic anterior ischemic optic neuropathy and primary open-angle glaucoma eyes had similar visual field mean deviation and peripapillary retinal nerve fiber layer thickness (P = 0.6 and P = 0.56, respectively). Bruch's membrane opening diameter was significantly larger in primary open-angle glaucoma eyes than in control eyes (P = 0.02). Lamina cribrosa and disk cup were deeper in eyes with primary open-angle glaucoma than both control and non-arteritic anterior ischemic optic neuropathy eyes (P < 0.001). Prelaminar tissue thickness was significantly thinner in primary open-angle glaucoma eyes than in non-arteritic anterior ischemic optic neuropathy eyes (P < 0.001). Lamina cribrosa was shallower in both non-arteritic anterior ischemic optic neuropathy and unaffected fellow eyes compared to healthy eyes (P < 0.001 and P = 0.04, respectively). No differences were found in the optic disk area. A forward lamina cribrosa placement and not a smaller disk could be involved in the pathogenesis of non-arteritic anterior ischemic optic neuropathy. A significantly larger Bruch's membrane opening diameter was found in primary open-angle glaucoma eyes compared with control eyes. This issue has clinical implications because Bruch's membrane opening has been considered a stable reference for disk-related measures.

  14. Contact Modelling of Large Radius Air Bending with Geometrically Exact Contact Algorithm

    NASA Astrophysics Data System (ADS)

    Vorkov, V.; Konyukhov, A.; Vandepitte, D.; Duflou, J. R.

    2016-08-01

    Usage of high-strength steels in conventional air bending is restricted due to limited bendability of these metals. Large-radius punches provide a typical approach for decreasing deformations during the bending process. However, as deflection progresses the loading scheme changes gradually. Therefore, modelling of the contact interaction is essential for an accurate description of the loading scheme. In the current contribution, the authors implemented a plane frictional contact element based on the penalty method. The geometrically exact contact algorithm is used for the penetration determination. The implementation is done using the OOFEM - open source finite element solver. In order to verify the simulation results, experiments have been conducted on a bending press brake for 4 mm Weldox 1300 with a punch radius of 30 mm and a die opening of 80 mm. The maximum error for the springback calculation is 0.87° for the bending angle of 144°. The contact interaction is a crucial part of large radius bending simulation and the implementation leads to a reliable solution for the springback angle.

  15. Patellofemoral Osteoarthritis Progression and Alignment Changes after Open-Wedge High Tibial Osteotomy Do Not Affect Clinical Outcomes at Mid-term Follow-up.

    PubMed

    Goshima, Kenichi; Sawaguchi, Takeshi; Shigemoto, Kenji; Iwai, Shintaro; Nakanishi, Akira; Ueoka, Ken

    2017-10-01

    To evaluate the clinical and radiological outcomes of open-wedge high tibial osteotomy (OWHTO) with respect to the patellofemoral joint and to assess whether patellofemoral osteoarthritis (OA) progression and alignment changes after OWHTO affect clinical outcomes. Inclusion criteria were consecutive patients who underwent OWHTO from March 2005 to September 2013. Exclusion criteria were loss to follow-up within 2 years and absence of second-look arthroscopy findings at the time of plate removal. The clinical parameters, including anterior knee pain while climbing stairs, Japanese Orthopedic Association score, and Oxford Knee Score, were evaluated. Radiological outcomes, including weight-bearing line ratio, modified Blackburne-Peel ratio, posterior tibial slope, tilting angle, lateral shift ratio, and patellofemoral OA (Kellgren-Lawrence grade), were evaluated preoperatively and at the final follow-up. Cartilage status (International Cartilage Repair Society grade) was evaluated at the initial HTO and at plate removal. Fifty-three patients (60 knees) were included in this study. The mean follow-up was 58.2 ± 22.4 months. Two knees (3%) presented with mild anterior knee pain after OWHTO. The mean Japanese Orthopedic Association score (66.9 ± 11.2 to 91.2 ± 9.7) significantly improved (P < .001), and the mean Oxford Knee Score at the final follow-up was 42.0 ± 5.3. The mean modified Blackburne-Peel ratio (0.9 ± 0.1 to 0.7 ± 0.1, P < .001) and tilting angle (6.8 ± 3.7 to 5.6 ± 3.4, P = .033) significantly decreased after OWHTO, whereas no significant changes in posterior tibial slope (P = .511) and lateral shift ratio (P = .522) were observed. Radiologically, patellofemoral OA had progressed in 15 knees (27%), and arthroscopically patellofemoral cartilage degeneration had progressed in 27 knees (45%). However, there was no significant correlation between changes in patellofemoral alignment and clinical outcomes. Changes in patellofemoral alignment and patellofemoral OA progression did not affect the clinical outcomes of OWHTO at mid-term follow-up. Level IV, therapeutic case series. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  16. Relationship between visual field progression and baseline refraction in primary open-angle glaucoma.

    PubMed

    Naito, Tomoko; Yoshikawa, Keiji; Mizoue, Shiro; Nanno, Mami; Kimura, Tairo; Suzumura, Hirotaka; Umeda, Yuzo; Shiraga, Fumio

    2016-01-01

    To analyze the relationship between visual field (VF) progression and baseline refraction in Japanese patients with primary open-angle glaucoma (POAG) including normal-tension glaucoma. In this retrospective study, the subjects were patients with POAG who had undergone VF tests at least ten times with a Humphrey Field Analyzer (Swedish interactive thresholding algorithm standard, Central 30-2 program). VF progression was defined as a significantly negative value of mean deviation (MD) slope at the final VF test. Multivariate logistic regression models were applied to detect an association between MD slope deterioration and baseline refraction. A total of 156 eyes of 156 patients were included in this analysis. Significant deterioration of MD slope was observed in 70 eyes of 70 patients (44.9%), whereas no significant deterioration was evident in 86 eyes of 86 patients (55.1%). The eyes with VF progression had significantly higher baseline refraction compared to those without apparent VF progression (-1.9±3.8 diopter [D] vs -3.5±3.4 D, P=0.0048) (mean ± standard deviation). When subject eyes were classified into four groups by the level of baseline refraction applying spherical equivalent (SE): no myopia (SE > -1D), mild myopia (-1D ≥ SE > -3D), moderate myopia (-3D ≥ SE > -6D), and severe myopia (-6D ≥ SE), the Cochran-Armitage trend analysis showed a decreasing trend in the proportion of MD slope deterioration with increasing severity of myopia (P=0.0002). The multivariate analysis revealed that baseline refraction (P=0.0108, odds ratio [OR]: 1.13, 95% confidence interval [CI]: 1.03-1.25) and intraocular pressure reduction rate (P=0.0150, OR: 0.97, 95% CI: 0.94-0.99) had a significant association with MD slope deterioration. In the current analysis of Japanese patients with POAG, baseline refraction was a factor significantly associated with MD slope deterioration as well as intraocular pressure reduction rate. When baseline refraction was classified into four groups, MD slope in myopia groups was less deteriorated as compared to those in the emmetropic/hyperopic group.

  17. Five-Year Incidence of Primary Open-Angle Glaucoma and Rate of Progression in Health Center-Based Korean Population: The Gangnam Eye Study

    PubMed Central

    Jeoung, Jin Wook; Park, Ki Ho; Kim, Dong Myung

    2014-01-01

    Objective To investigate the 5-year incidence and progression rate of primary open-angle glaucoma (POAG) in a health-center-based Korean population. Methods The study population comprised 5,021 subjects who participated in standardized health screening (including non-contact tonometry and fundus photography) at the Gangnam Healthcare Center during the period from January 2005 to December 2006 and again from January 2010 to December 2011. Among these subjects, 948 (18.9%) with findings suggestive of glaucoma were subjected to a comprehensive glaucoma evaluation, which included applanation tonometry and standard automated perimetry. Based on the results, the subjects were diagnosed as POAG suspect or definite POAG. Results The 5-year incidences of POAG suspect and definite POAG were 0.84% (42 subjects) and 0.72% (36 subjects), respectively. The rate of progression from POAG suspect to definite POAG was 4.75% per year. In subjects with a baseline intraocular pressure (IOP) >21 mmHg, the incidence of POAG suspect or definite POAG was significantly higher than in those with a baseline IOP≤21 mmHg (32% vs. 1.05%; P<0.001). A multivariate analysis showed that the progression from POAG suspect to definite POAG was significantly associated with older age (odds ratio [OR], 1.07; 95% confidence interval [CI], 1.03–1.10), higher baseline IOP (OR, 1.10; 95% CI, 1.01–1.24), higher body mass index (BMI) (OR, 1.15; 95% CI, 1.03–1.31), higher education level (OR, 1.57; 95% CI, 1.05–2.17), and higher hematocrit level (OR, 1.22; 95% CI, 1.08–1.43). Conclusions In the health-center-based Korean population, the 5-year incidence of POAG was 0.72%, and the rate of progression from POAG suspect to definite POAG was 4.75% per year. This study identified old age, high baseline IOP, high BMI, high level of education, and high hematocrit level as significant risk factors for incident POAG. PMID:25474589

  18. On the evolution of jet energy and opening angle in strongly coupled plasma

    NASA Astrophysics Data System (ADS)

    Chesler, Paul M.; Rajagopal, Krishna

    2016-05-01

    We calculate how the energy and the opening angle of jets in {N} = 4 SYM theory evolve as they propagate through the strongly coupled plasma of that theory. We define the rate of energy loss dE jet /dx and the jet opening angle in a straightforward fashion directly in the gauge theory before calculating both holographically, in the dual gravitational description. In this way, we rederive the previously known result for dE jet /dx without the need to introduce a finite slab of plasma. We obtain a striking relationship between the initial opening angle of the jet, which is to say the opening angle that it would have had if it had found itself in vacuum instead of in plasma, and the thermalization distance of the jet. Via this relationship, we show that {N} = 4 SYM jets with any initial energy that have the same initial opening angle and the same trajectory through the plasma experience the same fractional energy loss. We also provide an expansion that describes how the opening angle of the {N} = 4 SYM jets increases slowly as they lose energy, over the fraction of their lifetime when their fractional energy loss is not yet large. We close by looking ahead toward potential qualitative lessons from our results for QCD jets produced in heavy collisions and propagating through quark-gluon plasma.

  19. On the evolution of jet energy and opening angle in strongly coupled plasma

    DOE PAGES

    Chesler, Paul M.; Rajagopal, Krishna

    2016-05-17

    We calculate how the energy and the opening angle of jets in N = 4SYM theory evolve as they propagate through the strongly coupled plasma of that theory. We define the rate of energy loss dE jet/dx and the jet opening angle in a straightforward fashion directly in the gauge theory before calculating both holographically, in the dual gravitational description. In this way, we rederive the previously known result for dE jet/dx without the need to introduce a finite slab of plasma. We obtain a striking relationship between the initial opening angle of the jet, which is to say themore » opening angle that it would have had if it had found itself in vacuum instead of in plasma, and the thermalization distance of the jet. Via this relationship, we show that N = 4SYM jets with any initial energy that have the same initial opening angle and the same trajectory through the plasma experience the same fractional energy loss. We also provide an expansion that describes how the opening angle of the N = 4SYM jets increases slowly as they lose energy, over the fraction of their lifetime when their fractional energy loss is not yet large. In conclusion, we close by looking ahead toward potential qualitative lessons from our results for QCD jets produced in heavy collisions and propagating through quark-gluon plasma.« less

  20. Anterior segment parameters as predictors of intraocular pressure reduction after phacoemulsification in eyes with open-angle glaucoma.

    PubMed

    Hsia, Yen C; Moghimi, Sasan; Coh, Paul; Chen, Rebecca; Masis, Marisse; Lin, Shan C

    2017-07-01

    To evaluate intraocular pressure (IOP) change after cataract surgery in eyes with open-angle glaucoma (OAG) and its relationship to angle and anterior segment parameters measured by anterior segment optical coherence tomography (AS-OCT). University of California, San Francisco, California, USA. Prospective case series. Eyes were placed into a narrow-angle group or open-angle group based on gonioscopy grading. Biometric parameters were measured using AS-OCT (Visante) preoperatively, and IOP 4 months after surgery was obtained. The IOP change and its relationship to AS-OCT parameters were evaluated. Eighty-one eyes of 69 patients were enrolled. The mean age of the patients was 76.8 years. The preoperative IOP was 15.02 mm Hg on 1.89 glaucoma medications. The average mean deviation of preoperative visual field was -4.58 dB. The mean IOP reduction was 2.1 mm Hg (12.8%) from a preoperative mean of 15.0 mm Hg. The IOP reduction was significantly greater in eyes with narrow angles than in eyes with open angles (20.4% versus 8.0%) (P = .002). In multivariate analysis, preoperative IOP (β = -0.53, P < .001, R 2  = 0.40), angle-opening distance at 500 mm (β = 5.83, P = .02, R 2  = 0.45), angle-opening distance at 750 mm (β = 5.82, P = .001, R 2  = 0.52), and lens vault (β = -0.002, P = .009, R 2  = 0.47) were associated with IOP reduction postoperatively. In eyes with OAG, IOP reduction after cataract surgery was greater in eyes with narrower angles. Preoperative IOP, angle-opening distance, and lens vault were predictors for IOP reduction. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  1. A Generalized Maxwell Model for Creep Behavior of Artery Opening Angle

    PubMed Central

    Zhang, W.; Guo, X.; Kassab, G. S.

    2009-01-01

    An artery ring springs open into a sector after a radial cut. The opening angle characterizes the residual strain in the unloaded state, which is fundamental to understanding stress and strain in the vessel wall. A recent study revealed that the opening angle decreases with time if the artery is cut from the loaded state, while it increases if the cut is made from the no-load state due to viscoelasticity. In both cases, the opening angle approaches the same value in 3 hours. This implies that the characteristic relaxation time is about 10,000 sec. Here, the creep function of a generalized Maxwell model (a spring in series with six Voigt bodies) is used to predict the temporal change of opening angle in multiple time scales. It is demonstrated that the theoretical model captures the salient features of the experimental results. The proposed creep function may be extended to study the viscoelastic response of blood vessels under various loading conditions. PMID:19045526

  2. The distinction between juvenile and adult-onset primary open-angle glaucoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wiggs, J.L.; Haines, J.L.; Damji, K.F.

    1996-01-01

    Because of the significant differences between the juvenile and adult forms of open-angle glaucoma, especially with regard to inheritance, prevalence, severity, and age of onset, we read with interest the recent publication by Morissette et al., describing a pedigree with a phenotype that overlaps the distinctive features of juvenile-onset open-angle glaucoma (JOAG) and adult-onset primary open-angle glaucoma (usually abbreviated as POAG or COAG). These authors conclude that a gene mapped to human chromosome 1q21-q31 (GLC1A) can be responsible for both juvenile and adult forms of open-angle glaucoma. The implications of such a result could be extremely important, in light ofmore » the high prevalence of the adult form of the disease. However, while the data presented in this report suggest that variable expressivity of the GLC1A gene may lead to a broader range of onset for this form of juvenile glaucoma, these data do not identify the GLC1A gene as an important cause of POAG. To prevent misleading interpretations of this and similar studies, we wish to clarify the distinction between the juvenile and adult forms of open-angle glaucoma. 8 refs.« less

  3. Factors associated with postoperative C5 palsy after expansive open-door laminoplasty: retrospective cohort study using multivariable analysis.

    PubMed

    Tsuji, Takashi; Matsumoto, Morio; Nakamura, Masaya; Ishii, Ken; Fujita, Nobuyuki; Chiba, Kazuhiro; Watanabe, Kota

    2017-09-01

    The aim of the present study was to investigate the factors associated with C5 palsy by focusing on radiological parameters using multivariable analysis. The authors retrospectively assessed 190 patients with cervical spondylotic myelopathy treated by open-door laminoplasty. Four radiographic parameters-the number of expanded lamina, C3-C7 angle, lamina open angle and space anterior to the spinal cord-were evaluated to clarify the factors associated with C5 palsy. Of the 190 patients, 11 developed C5 palsy, giving an overall incidence of 5.8%. Although the number of expanded lamina, lamina open angle and space anterior to the spinal cord were significantly larger in C5 palsy group than those in non-palsy group, a multiple logistic regression analysis revealed that only the space anterior to the spinal cord (odds ratio 2.60) was a significant independent factor associated with C5 palsy. A multiple linear regression analysis indicated that the lamina open angle was associated with the space anterior to the spinal cord and the analysis identified the following equation: space anterior to the spinal cord (mm) = 1.54 + 0.09 × lamina open angle (degree). A cut-off value of 53.5° for the lamina open angle predicted the development of C5 palsy with a sensitivity of 72.7% and a specificity of 83.2%. The larger postoperative space anterior to the spinal cord, which was associated with the lamina open angle, was positively correlated with the higher incidence of C5 palsy.

  4. Cobb Angle Progression in Adolescent Scoliosis Begins at the Intervertebral Disc

    PubMed Central

    Will, Ryan E; Stokes, Ian A; Qiu, Xing; Walker, Matthew R.; Sanders, James O

    2009-01-01

    Study Design Longitudinal radiographic study of patients with progressive idiopathic scoliosis. Objective To determine the relative contributions of vertebral and disc wedging to the increase in Cobb angle during 3 phases of adolescent skeletal growth and maturation. Summary of Background Data Both disc wedging and vertebral body wedging are found in progressive scoliosis, but their relative contribution to curve progression over time is unknown. Which occurs first is important for understanding how scoliosis progresses and for developing methods to halt progression. Previous studies have not properly identified maturity and provide conflicting results. Methods Eighteen girls were followed through their adolescent growth spurt with serial spine and hand skeletal age radiographs. Each Cobb angle was divided into disc wedge angles and vertebral wedge angles. The corresponding hand radiographs provided a measure of maturity level, the Digital Skeletal Age (DSA). The disc versus bone contributions to the Cobb angle were then compared during 3 growth phases: prior to the growth spurt, during the growth spurt and after the growth spurt. Significance of relative changes was assessed with the Wilcoxon two-sided mean rank test. Results Prior to the growth spurt, there was no difference in relative contributions of the disc and the bone (3° vs 0°, p=0.38) to curve progression. During the growth spurt, the mean disc component progressed significantly more than that of the vertebrae (15° vs 0°, p=0.0002). This reversed following the growth spurt with the vertebral component progressing more than the disc (10° vs 0°, p=0.01). Conclusion Adolescent idiopathic scoliosis initially increases through disc wedging during the rapid growth spurt with progressive vertebral wedging occurring later. PMID:19940737

  5. Changes in Anterior Segment Morphology and Predictors of Angle Widening after Laser Iridotomy in South Indian Eyes.

    PubMed

    Zebardast, Nazlee; Kavitha, Srinivasan; Krishnamurthy, Palaniswamy; Friedman, David S; Nongpiur, Monisha E; Aung, Tin; Quigley, Harry A; Ramulu, Pradeep Y; Venkatesh, Rengaraj

    2016-12-01

    To compare anterior segment optical coherence tomography (ASOCT) angle morphology before and after laser peripheral iridotomy (LPI) in a cohort of South Indian subjects with primary angle-closure suspect (PACS) or primary angle-closure/primary angle-closure glaucoma (PAC/PACG) and to examine baseline parameters associated with angle widening. Prospective observational study. A total of 244 subjects aged ≥30 years with PACS or PAC/PACG in at least 1 eye. The ASOCT images and angle gonioscopic grades were analyzed for all subjects at baseline and 2 weeks after LPI. Multivariable linear and logistic regression models were used to determine predictors of angle widening (change in mean angle opening distance [AOD750]) and angle opening (all 4 quadrants with trabecular meshwork [TM] visible on gonioscopy after LPI). Change in ASOCT parameters with LPI and baseline predictors of angle widening. Laser peripheral iridotomy resulted in angle widening on ASOCT with significant increases in AOD750, angle recess area, and trabecular iris surface area (P < 0.05 for all). Gonioscopically, 44.7% of all subjects had open angles in all 4 quadrants after LPI, with a greater percentage of angles open in the PACS group compared with the PAC/PACG group (52.4% vs. 36.4%; P = 0.01). In multivariable regression analyses, greater postoperative angle widening as defined by change in AOD750 was associated with shorter baseline AOD750 and axial length, and greater baseline anterior chamber depth, iris curvature, and lens vault (P ≤ 0.002 for all). Gonioscopic angle opening after LPI was more common with wider baseline angle width (modified Shaffer grade) and lower cup-to-disc ratio (P < 0.001 for both). In a South Indian population with PACS or PAC/PACG, LPI results in significant anterior chamber angle widening seen on both ASOCT and gonioscopy, although some degree of persistent iridotrabecular contact was present in approximately half of PACS eyes and approximately two thirds of PAC/PACG eyes on gonioscopy. The greatest widening by ASOCT was observed in eyes with features most consistent with greater baseline pupillary block. Copyright © 2016 American Academy of Ophthalmology. All rights reserved.

  6. Effect of Foot Progression Angle and Lateral Wedge Insole on a Reduction in Knee Adduction Moment.

    PubMed

    Tokunaga, Ken; Nakai, Yuki; Matsumoto, Ryo; Kiyama, Ryoji; Kawada, Masayuki; Ohwatashi, Akihiko; Fukudome, Kiyohiro; Ohshige, Tadasu; Maeda, Tetsuo

    2016-10-01

    This study evaluated the effect of foot progression angle on the reduction in knee adduction moment caused by a lateral wedged insole during walking. Twenty healthy, young volunteers walked 10 m at their comfortable velocity wearing a lateral wedged insole or control flat insole in 3 foot progression angle conditions: natural, toe-out, and toe-in. A 3-dimensional rigid link model was used to calculate the external knee adduction moment, the moment arm of ground reaction force to knee joint center, and the reduction ratio of knee adduction moment and moment arm. The result indicated that the toe-out condition and lateral wedged insole decreased the knee adduction moment in the whole stance phase. The reduction ratio of the knee adduction moment and the moment arm exhibited a close relationship. Lateral wedged insoles decreased the knee adduction moment in various foot progression angle conditions due to decrease of the moment arm of the ground reaction force. Moreover, the knee adduction moment during the toe-out gait with lateral wedged insole was the smallest due to the synergistic effect of the lateral wedged insole and foot progression angle. Lateral wedged insoles may be a valid intervention for patients with knee osteoarthritis regardless of the foot progression angle.

  7. Efficacy of nighttime brace in preventing progression of idiopathic scoliosis of less than 25°.

    PubMed

    Lateur, G; Grobost, P; Gerbelot, J; Eid, A; Griffet, J; Courvoisier, A

    2017-04-01

    The objective of the present study was to assess, at skeletal maturity, the efficacy of non-operative treatment by isolated nighttime brace in the prevention of progression of progressive idiopathic scoliosis of less than 25°. Isolated nighttime brace treatment is effective in the prevention of progression of mild progressive idiopathic scoliosis (Cobb<25°). A single-center retrospective study included 142 patients managed by nighttime brace for progressive idiopathic scoliosis with Cobb angle<25°, with assessment at skeletal maturity. Mean Cobb angle at start of treatment was 15.5° (range, 10-25°). Mean values for Cobb angle and sagittal parameters before treatment and at skeletal maturity were compared on Student t-test. Change in Cobb angle over time was also analyzed. Mean Cobb angle at skeletal maturity was 16.3°, showing significant increase over baseline (15.5°; P=0.04), although the difference was less than the uncertainty of measurement (±6°). In baseline Risser 0 or 1, mean change in Cobb angle at skeletal maturity (16.2°) was not significant (P=0.1). Cobb angle diminished in 26 cases (18%), increased in 24 (17%) and was unchanged in 92 (65%). The present study confirmed the efficacy of non-operative treatment by nighttime brace in mild progressive idiopathic scoliosis (<25°) in a large majority of cases. A nighttime brace thus seems to be an effective option for the treatment of adolescent scoliosis, ensuring a safe curve of around 20°. Level IV, retrospective study. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  8. Full-angle tomographic phase microscopy of flowing quasi-spherical cells.

    PubMed

    Villone, Massimiliano M; Memmolo, Pasquale; Merola, Francesco; Mugnano, Martina; Miccio, Lisa; Maffettone, Pier Luca; Ferraro, Pietro

    2017-12-19

    We report a reliable full-angle tomographic phase microscopy (FA-TPM) method for flowing quasi-spherical cells along microfluidic channels. This method lies in a completely passive optical system, i.e. mechanical scanning or multi-direction probing of the sample is avoided. It exploits the engineered rolling of cells while they are flowing along a microfluidic channel. Here we demonstrate significant progress with respect to the state of the art of in-flow TPM by showing a general extension to cells having almost spherical shapes while they are flowing in suspension. In fact, the adopted strategy allows the accurate retrieval of rotation angles through a theoretical model of the cells' rotation in a dynamic microfluidic flow by matching it with phase-contrast images resulting from holographic reconstructions. So far, the proposed method is the first and the only one that permits to get in-flow TPM by probing the cells with full-angle, achieving accurate 3D refractive index mapping and the simplest optical setup, simultaneously. Proof of concept experiments were performed successfully on human breast adenocarcinoma MCF-7 cells, opening the way for the full characterization of circulating tumor cells (CTCs) in the new paradigm of liquid biopsy.

  9. Successful brace treatment of Scheuermann's kyphosis with different angles

    PubMed Central

    Etemadifar, Mohammad Reza; Jamalaldini, Mohammad Hossein; Layeghi, Rasoul

    2017-01-01

    Background: Scheuermann's disease is regarded as the most common cause of structural hyperkyphosis within adolescents without any proper treatment. It may lead to progressive deformity and back pain which influences patient's quality of life during adolescence and adulthood. Treatment approach to Scheuermann's kyphosis has not been clearly defined due to its different definitions and obscure natural history. The goal of treatment is not only to prevent progression but also to obtain permanent correction. Bracing, especially Milwaukee brace and physiotherapy are two of the common nonoperative treatment modalities. Hence, the present study intended to evaluate the effectiveness of Milwaukee brace on progression control as well as correction of Scheuermann's kyphosis. Materials and Methods: In a retrospective, observational study, all the patients diagnosed with Scheuermann's kyphosis were reviewed in 2003–2013, who were treated by Milwaukee brace at a single center. There was a minimum of 2-year follow-up after completion of bracing, during which clinical and radiological parameters were identified and recorded. Results: The mean angle of kyphosis in these patients at the presentation was 63.24 ± 9.96 and at the end of this study was 36.5° ± 13.4° (P < 0.001). Moreover, mean improved angle in those patients with <75° of kyphosis was 25.26° ± 7.78° and in those with 75° or more than 75° of kyphosis was 26.77° ± 19.76° (P < 0.001). Conclusion: Conservative treatment with Milwaukee brace and physiotherapy was effective in our hand for halting kyphosis progression in 97.5% of Scheuermann's kyphosis, which could be advised for cases up to 90° of kyphosis before skeletal maturity. As a result, a trial of brace treatment could be recommended in patients with severe kyphosis (up to 90°) which can open a new insight in conservative treatment of Scheuermann's kyphosis. PMID:28694598

  10. Preservative-free versus preserved latanoprost eye drops in patients with open-angle glaucoma or ocular hypertension.

    PubMed

    Aptel, Florent; Choudhry, Reena; Stalmans, Ingeborg

    2016-08-01

    This study compared the efficacy, safety, and pharmacokinetics of a preservative-free latanoprost formulation to an established, benzalkonium chloride (BAK) containing formulation for the treatment of open-angle glaucoma or ocular hypertension. This was a phase II, randomized, cross-over, investigator-masked, multi-center, pilot study (NCT01494753). A total of 30 untreated adult patients (aged ≥18 years) with primary open angle glaucoma, pseudo-exfoliative glaucoma, pigmentary glaucoma, or ocular hypertension received either preservative-free or preserved latanoprost once daily in both eyes for 6 weeks, before crossing over to receive the other treatment. Efficacy (intraocular pressure [IOP] at 8 am, midday, 4 pm and 8 pm, and global efficacy assessment by investigator), safety (adverse events, ocular symptoms and global tolerance, slit lamp examination, funduscopy, visual field examination, visual acuity, and heart rate), and pharmacokinetics were assessed at Days 0, 42, and 84. Both treatments resulted in a reduction in IOP that was similar for the preservative-free and the preserved formulation at all time points. Similarly, the overall diurnal reduction was similar in both groups (6.3 mmHg [27.9% reduction] and 6.4 mmHg [28.1% reduction] for preserved and preservative-free latanoprost, respectively). There were no differences in global efficacy assessment or in the safety and tolerance of each treatment. Systemic concentrations of latanoprost were very low; AUC0-30 and Cmax were lower and tmax was longer for preservative-free latanoprost. Preservative-free latanoprost showed similar efficacy at all time points compared to BAK preservative containing formulation, with no difference in tolerance, allowing progression to phase III clinical development.

  11. Anatomical features of skull base and oral cavity: a pilot study to determine the accessibility of the sella by transoral robotic-assisted surgery.

    PubMed

    Amelot, Aymeric; Trunet, Stephanie; Degos, Vincent; André, Olivier; Dionnet, Aurore; Cornu, Philippe; Hans, Stéphane; Chauvet, Dorian

    2015-10-01

    The role of transoral robotic surgery (TORS) in the skull base emerges and represents the natural progression toward miniinvasive resections in confined spaces. The accessibility of the sella via TORS has been recently described on fresh human cadavers. An anatomic study is mandatory to know if this approach would be feasible in the majority of patients regardless of their oral morphological features. From 30 skull base CT scans from patients who were asked to open their mouth as wide as they can, we measured specific dimensions of the oral cavity and the skull base, such as length of the palate, mouth opening and distance from the sella to the palate. All data were acquired on a sagittal midline plane and on a 25° rotation plane, which simulated the axis of the robotic instruments. Looking at the projection of the dental palatine line on the sella, we studied possible predictive factors of sellar accessibility and tried to bring objective data for surgical feasibility. We also proposed an angle α to study the working angle at the skull base. We observed that the maximal mouth opening was a good predictive factor of sellar accessibility by TORS (p < 0.05). The mouth aperture threshold value for a good sensitivity, over 80 %, was comparable to the mean value of mouth opening in our series, 38.9 and 39.4 mm respectively. Moreover, we showed a statistically significant increase of the working angle α at the skull base comparing the lateral access to the midline one (p < 0.05). This seemed to quantitatively demonstrate that the robotic arms placed at the labial commissure of the mouth can reach the sella. From these anatomical features and previous cadaveric dissections, we assume that TORS may be feasible on a majority of patients to remove pituitary adenomas.

  12. Undetected angle closure in patients with a diagnosis of open-angle glaucoma.

    PubMed

    Varma, Devesh K; Simpson, Sarah M; Rai, Amandeep S; Ahmed, Iqbal Ike K

    2017-08-01

    The aim of this study was to identify the proportion of patients referred to a tertiary glaucoma centre with a diagnosis of open-angle glaucoma (OAG) who were found to have angle closure glaucoma. Retrospective chart review. Consecutive new patients referred for glaucoma management to a tertiary centre between July 2010 and December 2011 were reviewed. Patients whose referrals for glaucoma assessment specified angle status as "open" were included. The data collected included glaucoma specialist's angle assessment, diagnosis, and glaucoma severity. The status of those with 180 degrees or more Shaffer angle grading of 0 was classified as "closed." From 1234 glaucoma referrals, 179 cases were specified to have a diagnosis of OAG or when angles were known to be open. Of these, 16 (8.9%) were found on examination by the glaucoma specialist to have angle closure. Pseudoexfoliation was present in 4 of 16 patients (25%) in the missed angle-closure glaucoma (ACG) group and 22 of 108 patients (13.5%) in the remaining OAG group. There was no difference found in demographic or ocular biometric parameters between those with confirmed OAG versus those with missed ACG. Almost 1 in 11 patients referred by ophthalmologists to a tertiary glaucoma centre with a diagnosis of OAG were in fact found to have angle closure. Given the different treatment approaches for ACG versus OAG, this study suggests a need to strengthen angle evaluations. Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

  13. Monte Carlo-based assessment of the trade-off between spatial resolution, field-of-view and scattered radiation in the variable resolution X-ray CT scanner.

    PubMed

    Arabi, Hossein; Kamali Asl, Ali Reza; Ay, Mohammad Reza; Zaidi, Habib

    2015-07-01

    The purpose of this work is to evaluate the impact of optimization of magnification on performance parameters of the variable resolution X-ray (VRX) CT scanner. A realistic model based on an actual VRX CT scanner was implemented in the GATE Monte Carlo simulation platform. To evaluate the influence of system magnification, spatial resolution, field-of-view (FOV) and scatter-to-primary ratio of the scanner were estimated for both fixed and optimum object magnification at each detector rotation angle. Comparison and inference between these performance parameters were performed angle by angle to determine appropriate object position at each opening half angle. Optimization of magnification resulted in a trade-off between spatial resolution and FOV of the scanner at opening half angles of 90°-12°, where the spatial resolution increased up to 50% and the scatter-to-primary ratio decreased from 4.8% to 3.8% at a detector angle of about 90° for the same FOV and X-ray energy spectrum. The disadvantage of magnification optimization at these angles is the significant reduction of the FOV (up to 50%). Moreover, magnification optimization was definitely beneficial for opening half angles below 12° improving the spatial resolution from 7.5 cy/mm to 20 cy/mm. Meanwhile, the FOV increased by more than 50% at these angles. It can be concluded that optimization of magnification is essential for opening half angles below 12°. For opening half angles between 90° and 12°, the VRX CT scanner magnification should be set according to the desired spatial resolution and FOV. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  14. Lack of Association of Mutations in Optineurin With Disease in Patients With Adult-onset Primary Open-angle Glaucoma

    PubMed Central

    Wiggs, Janey L.; Auguste, Josette; Allingham, R. Rand; Flor, Jason D.; Pericak-Vance, Margaret A.; Rogers, Kathryn; LaRocque, Karen R.; Graham, Felicia L.; Broomer, Bob; Del Bono, Elizabeth; Haines, Jonathan L.; Hauser, Michael

    2005-01-01

    Objective: To determine whether mutations in the optineurin gene contribute to susceptibility to adult-onset primary open-angle glaucoma. Methods: The optineurin gene was screened in 86 probands with adult-onset primary open-angle glaucoma and in 80 age-matched control subjects. Exons 4 and 5, containing the recurrent mutations identified in patients with normal-tension glaucoma, were sequenced in all individuals studied, while the remaining exons were screened for DNA sequence variants with denaturing high-performance liquid chromatography. Results: The recurrent mutation, Met98Lys, previously found to be associated with an increased risk of disease was found in 8 (9%) of 86 probands. We also found the Met98Lys mutation in 10% of individuals from a control population of similar age, sex, and ethnicity. Consistent segregation of the mutation with the disease was not demonstrated in any of the 8 families. No other DNA changes altering the amino acid structure of the protein were found. Conclusion: The mutations in the optineurin gene associated with normal-tension glaucoma are not associated with adult-onset primary open-angle glaucoma in this patient population. Clinical Relevance: Genetic abnormalities that render the optic nerve susceptible to degeneration are excellent candidates for genetic factors that could contribute to adult-onset primary open-angle glaucoma. Mutations in optineurin have been associated with normal-tension glaucoma, but are not associated with disease in patients with adult-onset primary open-angle glaucoma. This result may indicate that normal-tension glaucoma is not necessarily part of the phenotypic spectrum of adult open-angle glaucoma. PMID:12912697

  15. Medical management of primary open-angle glaucoma: Best practices associated with enhanced patient compliance and persistency.

    PubMed

    Kulkarni, Sadhana V; Damji, Karim F; Buys, Yvonne M

    2008-02-02

    Primary open angle glaucoma is a chronic optic neuropathy often requiring lifelong treatment. Patient compliance, adherence and persistence with therapy play a vital role in improved outcomes by reducing morbidity and the economic consequences that are associated with disease progression. A literature review including searches of The Cochrane Library, MEDLINE, PubMed, conference proceedings, and bibliographies of identified articles reveals the enormous public health burden in various populations due to the impact of glaucoma associated visual impairment on the overall quality of life eg, fear of blindness, inability to work in certain occupations, driving restrictions, motor vehicle accidents, falls, and general health status. Providing specific definitions for the frequently misunderstood terms "compliance, persistence and adherence" with reference to medication use is central not only for monitoring patients' drug dosing histories and clinical outcomes but also for subsequent research. In this review article, a summary of the advantages/disadvantages including cost-effectiveness of various medical approaches to glaucoma treatment, techniques employed for measuring patient compliance and actual patient preferences for therapy are outlined. We conclude by identifying the key barriers to ongoing treatment and suggest some best practices to enhance compliance and persistence.

  16. Medical management of primary open-angle glaucoma: Best practices associated with enhanced patient compliance and persistency

    PubMed Central

    Kulkarni, Sadhana V; Damji, Karim F; Buys, Yvonne M

    2008-01-01

    Primary open angle glaucoma is a chronic optic neuropathy often requiring lifelong treatment. Patient compliance, adherence and persistence with therapy play a vital role in improved outcomes by reducing morbidity and the economic consequences that are associated with disease progression. A literature review including searches of The Cochrane Library, MEDLINE, PubMed, conference proceedings, and bibliographies of identified articles reveals the enormous public health burden in various populations due to the impact of glaucoma associated visual impairment on the overall quality of life eg, fear of blindness, inability to work in certain occupations, driving restrictions, motor vehicle accidents, falls, and general health status. Providing specific definitions for the frequently misunderstood terms “compliance, persistence and adherence” with reference to medication use is central not only for monitoring patients’ drug dosing histories and clinical outcomes but also for subsequent research. In this review article, a summary of the advantages/disadvantages including cost-effectiveness of various medical approaches to glaucoma treatment, techniques employed for measuring patient compliance and actual patient preferences for therapy are outlined. We conclude by identifying the key barriers to ongoing treatment and suggest some best practices to enhance compliance and persistence. PMID:19920977

  17. Anterior Segment Imaging Predicts Incident Gonioscopic Angle Closure.

    PubMed

    Baskaran, Mani; Iyer, Jayant V; Narayanaswamy, Arun K; He, Yingke; Sakata, Lisandro M; Wu, Renyi; Liu, Dianna; Nongpiur, Monisha E; Friedman, David S; Aung, Tin

    2015-12-01

    To investigate the incidence of gonioscopic angle closure after 4 years in subjects with gonioscopically open angles but varying degrees of angle closure detected on anterior segment optical coherence tomography (AS OCT; Visante; Carl Zeiss Meditec, Dublin, CA) at baseline. Prospective, observational study. Three hundred forty-two subjects, mostly Chinese, 50 years of age or older, were recruited, of whom 65 were controls with open angles on gonioscopy and AS OCT at baseline, and 277 were cases with baseline open angles on gonioscopy but closed angles (1-4 quadrants) on AS OCT scans. All subjects underwent gonioscopy and AS OCT at baseline (horizontal and vertical single scans) and after 4 years. The examiner performing gonioscopy was masked to the baseline and AS OCT data. Angle closure in a quadrant was defined as nonvisibility of the posterior trabecular meshwork by gonioscopy and visible iridotrabecular contact beyond the scleral spur in AS OCT scans. Gonioscopic angle closure in 2 or 3 quadrants after 4 years. There were no statistically significant differences in age, ethnicity, or gender between cases and controls. None of the control subjects demonstrated gonioscopic angle closure after 4 years. Forty-eight of the 277 subjects (17.3%; 95% confidence interval [CI], 12.8-23; P < 0.0001) with at least 1 quadrant of angle closure on AS OCT at baseline demonstrated gonioscopic angle closure in 2 or more quadrants, whereas 28 subjects (10.1%; 95% CI, 6.7-14.6; P < 0.004) demonstrated gonioscopic angle closure in 3 or more quadrants after 4 years. Individuals with more quadrants of angle closure on baseline AS OCT scans had a greater likelihood of gonioscopic angle closure developing after 4 years (P < 0.0001, chi-square test for trend for both definitions of angle closure). Anterior segment OCT imaging at baseline predicts incident gonioscopic angle closure after 4 years among subjects who have gonioscopically open angles and iridotrabecular contact on AS OCT at baseline. Copyright © 2015 American Academy of Ophthalmology. All rights reserved.

  18. Comparison of Different Methods of Grading a Level Turn Task on a Flight Simulator

    NASA Technical Reports Server (NTRS)

    Heath, Bruce E.; Crier, tomyka

    2003-01-01

    With the advancements in the computing power of personal computers, pc-based flight simulators and trainers have opened new avenues in the training of airplane pilots. It may be desirable to have the flight simulator make a quantitative evaluation of the progress of a pilot's training thereby reducing the physical requirement of the flight instructor who must, in turn, watch every flight. In an experiment, University students conducted six different flights, each consisting of two level turns. The flights were three minutes in duration. By evaluating videotapes, two certified flight instructors provided separate letter grades for each turn. These level turns were also evaluated using two other computer based grading methods. One method determined automated grades based on prescribed tolerances in bank angle, airspeed and altitude. The other method used was deviations in altitude and bank angle for performance index and performance grades.

  19. Open arthrolysis for elbow stiffness increases carrying angle but has no impact on functional recovery.

    PubMed

    Fan, Dapeng; Wang, Wei; Hildebrand, Kevin A; Fan, Cun-Yi

    2016-09-09

    With the exception of normal anatomic changes in the medial collateral ligament and radial head, other factors related to carrying angle changes have not been systematically studied. We reviewed patients who underwent open arthrolysis of the elbow, and evaluated if open arthrolysis could change carrying angle. We then identified factors associated with carrying angle changes. Fifty patients with a minimum of 24 months of follow-up after open arthrolysis were evaluated retrospectively. Preoperative and postoperative carrying angles were compared. The carrying angles of 36 elbows in 36 patients were unchanged after surgery (Group A), while the carrying angles of 14 elbows in 14 patients increased postoperatively (Group B). In Group A, mean postoperative extension and flexion were 7° (range 0-24°) and 125° (range 10-135°) respectively, while mean postoperative pronation and supination were 60° (range 50-80°) and 65° (range 30-85°), respectively. In Group B, mean postoperative extension and flexion were 25° (range 0-40°) and 128° (range 60-138°), while mean postoperative pronation and supination were 65° (range 45-85°) and 60° (range 45-75°), respectively. No significant difference in range of motion and Mayo Elbow Performance Score was observed between the two groups. During open arthrolysis, humeral trochlea debridement and techniques for improving forearm rotation could increase carrying angle. However, this had no impact on elbow functional recovery.

  20. Obstructive sleep apnoea syndrome in patients with primary open-angle glaucoma.

    PubMed

    Balbay, Ege G; Balbay, Oner; Annakkaya, Ali N; Suner, Kezban O; Yuksel, Harun; Tunç, Murat; Arbak, Peri

    2014-10-01

    To investigate the prevalence of obstructive sleep apnoea syndrome in patients with primary open-angle glaucoma. Case series. School of Medicine, Düzce University, Turkey. Twenty-one consecutive primary open-angle glaucoma patients (12 females and 9 males) who attended the out-patient clinic of the Department of Ophthalmology between July 2007 and February 2008 were included in this study. All patients underwent polysomnographic examination. The prevalence of obstructive sleep apnoea syndrome was 33.3% in patients with primary open-angle glaucoma; the severity of the condition was mild in 14.3% and moderate in 19.0% of the subjects. The age (P=0.047) and neck circumference (P=0.024) in patients with obstructive sleep apnoea syndrome were significantly greater than those without the syndrome. Triceps skinfold thickness in glaucomatous obstructive sleep apnoea syndrome patients reached near significance versus those without the syndrome (P=0.078). Snoring was observed in all glaucoma cases with obstructive sleep apnoea syndrome. The intra-ocular pressure of patients with primary open-angle glaucoma with obstructive sleep apnoea syndrome was significantly lower than those without obstructive sleep apnoea syndrome (P=0.006 and P=0.035 for the right and left eyes, respectively). There was no significant difference in the cup/disc ratio and visual acuity, except visual field defect, between primary open-angle glaucoma patients with and without obstructive sleep apnoea syndrome. Although it does not provide evidence for a cause-effect relationship, high prevalence of obstructive sleep apnoea syndrome in patients with primary open-angle glaucoma in this study suggests the need to explore the long-term results of coincidence, relationship, and cross-interaction of these two common disorders.

  1. Tank-Binding Kinase 1 (TBK1) Gene and Open-Angle Glaucomas (An American Ophthalmological Society Thesis)

    PubMed Central

    Fingert, John H.; Robin, Alan L.; Scheetz, Todd E.; Kwon, Young H.; Liebmann, Jeffrey M.; Ritch, Robert; Alward, Wallace L.M.

    2016-01-01

    Purpose To investigate the role of TANK-binding kinase 1 (TBK1) gene copy-number variations (ie, gene duplications and triplications) in the pathophysiology of various open-angle glaucomas. Methods In previous studies, we discovered that copy-number variations in the TBK1 gene are associated with normal-tension glaucoma. Here, we investigated the prevalence of copy-number variations in cohorts of patients with other open-angle glaucomas—juvenile-onset open-angle glaucoma (n=30), pigmentary glaucoma (n=209), exfoliation glaucoma (n=225), and steroid-induced glaucoma (n=79)—using a quantitative polymerase chain reaction assay. Results No TBK1 gene copy-number variations were detected in patients with juvenile-onset open-angle glaucoma, pigmentary glaucoma, or steroid-induced glaucoma. A TBK1 gene duplication was detected in one (0.44%) of the 225 exfoliation glaucoma patients. Conclusions TBK1 gene copy-number variations (gene duplications and triplications) have been previously associated with normal-tension glaucoma. An exploration of other open-angle glaucomas detected a TBK1 copy-number variation in a patient with exfoliation glaucoma, which is the first example of a TBK1 mutation in a glaucoma patient with a diagnosis other than normal-tension glaucoma. A broader phenotypic range may be associated with TBK1 copy-number variations, although mutations in this gene are most often detected in patients with normal-tension glaucoma. PMID:27881886

  2. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chesler, Paul M.; Rajagopal, Krishna

    We calculate how the energy and the opening angle of jets in N = 4SYM theory evolve as they propagate through the strongly coupled plasma of that theory. We define the rate of energy loss dE jet/dx and the jet opening angle in a straightforward fashion directly in the gauge theory before calculating both holographically, in the dual gravitational description. In this way, we rederive the previously known result for dE jet/dx without the need to introduce a finite slab of plasma. We obtain a striking relationship between the initial opening angle of the jet, which is to say themore » opening angle that it would have had if it had found itself in vacuum instead of in plasma, and the thermalization distance of the jet. Via this relationship, we show that N = 4SYM jets with any initial energy that have the same initial opening angle and the same trajectory through the plasma experience the same fractional energy loss. We also provide an expansion that describes how the opening angle of the N = 4SYM jets increases slowly as they lose energy, over the fraction of their lifetime when their fractional energy loss is not yet large. In conclusion, we close by looking ahead toward potential qualitative lessons from our results for QCD jets produced in heavy collisions and propagating through quark-gluon plasma.« less

  3. Tank-Binding Kinase 1 (TBK1) Gene and Open-Angle Glaucomas (An American Ophthalmological Society Thesis).

    PubMed

    Fingert, John H; Robin, Alan L; Scheetz, Todd E; Kwon, Young H; Liebmann, Jeffrey M; Ritch, Robert; Alward, Wallace L M

    2016-08-01

    To investigate the role of TANK-binding kinase 1 ( TBK1 ) gene copy-number variations (ie, gene duplications and triplications) in the pathophysiology of various open-angle glaucomas. In previous studies, we discovered that copy-number variations in the TBK1 gene are associated with normal-tension glaucoma. Here, we investigated the prevalence of copy-number variations in cohorts of patients with other open-angle glaucomas-juvenile-onset open-angle glaucoma (n=30), pigmentary glaucoma (n=209), exfoliation glaucoma (n=225), and steroid-induced glaucoma (n=79)-using a quantitative polymerase chain reaction assay. No TBK1 gene copy-number variations were detected in patients with juvenile-onset open-angle glaucoma, pigmentary glaucoma, or steroid-induced glaucoma. A TBK1 gene duplication was detected in one (0.44%) of the 225 exfoliation glaucoma patients. TBK1 gene copy-number variations (gene duplications and triplications) have been previously associated with normal-tension glaucoma. An exploration of other open-angle glaucomas detected a TBK1 copy-number variation in a patient with exfoliation glaucoma, which is the first example of a TBK1 mutation in a glaucoma patient with a diagnosis other than normal-tension glaucoma. A broader phenotypic range may be associated with TBK1 copy-number variations, although mutations in this gene are most often detected in patients with normal-tension glaucoma.

  4. Pigment dispersion syndrome and pigmentary glaucoma--a major review.

    PubMed

    Niyadurupola, Nuwan; Broadway, David C

    2008-12-01

    Pigment dispersion syndrome (PDS) is an interesting condition that can lead to secondary open angle glaucoma. Pigmentary glaucoma is primarily a disease of young people, myopes and men. PDS is characterized by the presence of Krukenberg spindles, iris trans-illumination defects, trabecular meshwork pigmentation and backward bowing of the iris. Posterior bowing of the iris causes rubbing of the pigmented iris epithelium against lens structures, liberation of pigment and trabecular meshwork changes that result in reduced aqueous outflow with the risk of glaucoma. Peripheral laser iridotomy can reverse backward bowing of the iris and may prevent progression of pigmentary glaucoma.

  5. Auditory processing deficits in individuals with primary open-angle glaucoma.

    PubMed

    Rance, Gary; O'Hare, Fleur; O'Leary, Stephen; Starr, Arnold; Ly, Anna; Cheng, Belinda; Tomlin, Dani; Graydon, Kelley; Chisari, Donella; Trounce, Ian; Crowston, Jonathan

    2012-01-01

    The high energy demand of the auditory and visual pathways render these sensory systems prone to diseases that impair mitochondrial function. Primary open-angle glaucoma, a neurodegenerative disease of the optic nerve, has recently been associated with a spectrum of mitochondrial abnormalities. This study sought to investigate auditory processing in individuals with open-angle glaucoma. DESIGN/STUDY SAMPLE: Twenty-seven subjects with open-angle glaucoma underwent electrophysiologic (auditory brainstem response), auditory temporal processing (amplitude modulation detection), and speech perception (monosyllabic words in quiet and background noise) assessment in each ear. A cohort of age, gender and hearing level matched control subjects was also tested. While the majority of glaucoma subjects in this study demonstrated normal auditory function, there were a significant number (6/27 subjects, 22%) who showed abnormal auditory brainstem responses and impaired auditory perception in one or both ears. The finding that a significant proportion of subjects with open-angle glaucoma presented with auditory dysfunction provides evidence of systemic neuronal susceptibility. Affected individuals may suffer significant communication difficulties in everyday listening situations.

  6. Progressive Retinal Nerve Fiber Layer Atrophy Associated With Enlarging Peripapillary Pit.

    PubMed

    Lee, Eun Ji; Kim, Tae-Woo

    2017-02-01

    To report a case in which progressive retinal nerve fiber layer (RNFL) atrophy was observed along with enlargement of the peripapillary pit. A 34-year-old male was diagnosed with primary open-angle glaucoma and followed up for 4 years with regular ophthalmic examinations. Both eyes were myopic (-10 D, OD and -10.5 D, OS), and untreated intraocular pressures were 18 mm Hg (OD) and 16 mm Hg (OS). A subtle depression of the superotemporal peripapillary area was deepened and emerged as a peripapillary pit during the follow-up period. With the enlargement of the peripapillary pit, a RNFL defect at the location of pit widened and thinned continuously. The enlargement of the pit was documented by the spectral-domain optical coherence tomography posterior pole scanning. Progressive RNFL atrophy was observed with enlargement of the peripapillary pit. The finding suggests that tensile stress derived from the scleral stretching may have significant influence on the integrity of the RNFL.

  7. The Influence of Structure Heights and Opening Angles of Micro- and Nanocones on the Macroscopic Surface Wetting Properties

    NASA Astrophysics Data System (ADS)

    Schneider, Ling; Laustsen, Milan; Mandsberg, Nikolaj; Taboryski, Rafael

    2016-02-01

    We discuss the influence of surface structure, namely the height and opening angles of nano- and microcones on the surface wettability. We show experimental evidence that the opening angle of the cones is the critical parameter on sample superhydrophobicity, namely static contact angles and roll-off angles. The textured surfaces are fabricated on silicon wafers by using a simple one-step method of reactive ion etching at different processing time and gas flow rates. By using hydrophobic coating or hydrophilic surface treatment, we are able to switch the surface wettability from superhydrophilic to superhydrophobic without altering surface structures. In addition, we show examples of polymer replicas (polypropylene and poly(methyl methacrylate) with different wettability, fabricated by injection moulding using templates of the silicon cone-structures.

  8. [21st century management of glaucoma].

    PubMed

    Tsukahara, Shigeo

    2003-12-01

    According to a recent epidemiological study done in Japan, 2 or 3 million Japanese people are thought to be suffering from glaucoma, and 70-80% of them have not been examined or diagnosed by ophthalmologists. Therefore, the problem is how to find these untreated and undiagnosed people. At present, treatment of glaucoma continues to be directed at lowering intraocular pressure to prevent progression of glaucomatous optic neuropathy. However, theoretically, there are three stages in the prevention of progression of glaucoma. In the first stage, diagnosis of glaucoma can be done by genetic examination, before occurrence of glaucoma. The MYOCILIN/trabecular meshwork-inducible glucocorticoid response gene and the optineurin gene were identified as the genes that cause open angle glaucoma. Although some Japanese patients have sequence changes in the myocilin gene, there are no apparent specific mutations in Japanese glaucoma patients, in the MYOCILIN/TIGR and optineurin genes. Secondary glaucoma such as steroid glaucoma, induced by allergic diseases, and neovascular glaucoma, induced by retinal circulatory insufficiency, are preventable by improving the causal diseases, diabetes and hypertension. The education of doctors and laymen is important to reduce the occurrence of diabetes, and hypertension to prevent diabetic retinopathy, and retinal vessel occlusion. The second stage in preventing progression of glaucoma is to find the disease as early as possible. In Japan, a physical examination system is in place for everybody over 40 years old, in companies and local districts. Therefore, ocular examination, specially non-mydriatic fundus photographs should be taken in these examinations, and the film should be evaluated by an ophthalmologist, to search for retinal and optic disc abnormalities. Primary open angle glaucoma can be detected through this system in early stages. In primary angle closure glaucoma, instruments for estimating anterior chamber rapidly and accurately are necessary for the diagnosis. There is a special machine which can be handled easily, safely, and economically for detecting angle closure glaucoma, has been developed by Yamanashi University. This machine might help to reduce the number of angle closure glaucoma patients in the world. In the near future, a glaucoma network system should be put in place all over Japan. This organization consists of central headquarter and local central office. Most hospitals and private offices will belong to a local central office, and several glaucoma specialists will work in central and local offices. All glaucoma patients will be registered in local glaucoma office. The information on glaucoma patients will be communicated in the system the through light fiber cables or a satellite system. The patients can ask about their own disease through this glaucoma center system. In the third stage of glaucoma prevention, progression of glaucomatous optic neuropathy is retarded by conventional IOP lowering treatment or neuroprotective drugs. This stage compromises rehabilitation of visual function, implant of artificial visual systems, and regeneration of retinal ganglion cells(RGC). The disturbances of axonal flow in guinea pig optic nerve fibers was demonstrated electromicroscopically by quick-freeze, deep-etching method and, the decrease in numbers of motor proteins like "Kinesin" "Dynein" and "MAP-1" was shown in guinea pig eyes with elevated intraocular pressure by immunohistochemistry. Retinal glanglion cells have been isolated and new findings have been reported using this RGC culture system. Therefore, new neuroprotective drugs will be developed through this culture system.

  9. Annual changes in radiographic indices of the spine in cerebral palsy patients.

    PubMed

    Lee, Seung Yeol; Chung, Chin Youb; Lee, Kyoung Min; Kwon, Soon-Sun; Cho, Kyu-Jung; Park, Moon Seok

    2016-03-01

    We estimated the annual changes in radiographic indices of the spine in cerebral palsy (CP) patients and analyzed the factors that influence its progression rate. We included CP patients who had undergone whole-spine radiography more than twice and were followed for at least 1 year. The scoliosis Cobb angle, coronal balance, apical vertebral translation, apical rotation, and pelvic obliquity were measured on anteroposterior (AP) radiographs; thoracic kyphosis and lumbar lordosis angles, and sagittal balance was measured on lateral radiographs; and migration percentage was measured on AP hip radiographs to determine hip instability. For each gross motor function classification system (GMFCS) level, the Cobb angles, apical vertebral translation, coronal and sagittal balance, and pelvic obliquity were adjusted by multiple factors with a linear mixed model. A total of 184 patients (774 radiographs) were included in this study. There was no significant annual change in scoliosis Cobb, thoracic kyphosis, and lumbar lordosis angles in the GMFCS level I-II and III groups. In the GMFCS level IV-V group, there was an annual increase of 3.4° in the scoliosis Cobb angle (p = 0.020). The thoracic kyphosis angle increased by 2.2° (p = 0.018) annually in the GMFCS level IV-V group. Apical vertebral translation increased by 5.4 mm (p = 0.029) annually in the GMFCS level IV-V group. Progression of coronal and sagittal balance and pelvic obliquity with aging were not statistically significant. Sex, hip instability, hip surgery, and triradiate cartilage did not affect the progression of scoliosis and the balance of the spine and pelvis. The scoliosis Cobb angle, thoracic kyphosis angle, and apical vertebral translation in the GMFCS level IV-V CP patients progressed with age. These findings can predict radiographic progression of scoliosis in CP patients.

  10. Effect of aperture geometry on heat transfer in tilted partially open cavities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Elsayed, M.M.; Chakroun, W.

    1999-11-01

    Heat transfer in cavities is receiving increasing attention because of the various applications in engineering; e.g., passive solar heating, energy conservation in buildings, solar concentrating receivers, and electronic equipment. Here, convection from a square, tilted partially open cavity was investigated experimentally. The experiment was carried out to study the effect of the aperture geometry on the heat transfer between the cavity and the surrounding air. Four different geometrical arrangements for the opening were investigated: (1) high wall slit, (2) low wall slit, (3) centered wall slit, and (4) uniform wall slots. Each opening arrangement was studied at opening ratios (i.e.,more » ratio of opening height to cavity height) of 0.25, 0.5, and 0.75. The average heat transfer coefficient between the cavity and the surrounding air was estimated for each geometrical arrangement for tilt angles ranging from {minus}90 deg to +90 deg with increments of 15 deg and at a constant heat flux Grashof number of 5.5 x 10{sup 8}. The results showed that for tilt angles between 90 and 75 deg, the heat transfer coefficient has a small value that is independent of the geometrical arrangement of the opening. The value of the heat transfer coefficient increases sharply with decreasing tilt angle until an angle value of zero degrees is reached. The increase in the heat transfer coefficient continues in the negative range of tilt angle but not in the same rate as in the positive range of the tilt angle. The uniform slot arrangement gave in general higher heat transfer coefficient than the other three arrangements of the opening. Large differences in the heat transfer coefficient were observed between the high and the low wall slits where the high wall slit is found to transfer more heat to the surroundings than the low wall slit. Correlations were developed to predict the average Nusselt number of the cavity in terms of the opening ratio and the cavity tilt angle for cavities with high wall slit, low wall slit, centered wall slit, and the uniform wall slots.« less

  11. Molecular genetics of the glaucomas: Mapping of the first five {open_quotes}GLC{close_quotes} loci

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Raymond, V.

    1997-02-01

    Glaucoma encompasses a complex of ocular-disease entities characterized by an optic neuropathy in which degeneration of retinal ganglion cells leads to a characteristic excavation of the head of the optic nerve. Such damage causes progressive narrowing of the visual fields and, when uncontrolled, blindness. Affected people often have ocular hypertension defined as intraocular pressures consistently >21 mm Hg in both eyes. Although ocular hypertension is no longer an obligatory diagnostic criterion for glaucoma, it is still recognized as one of the most important risk factors. A diagnosis of glaucoma is made after observation of the characteristic atrophy of the opticmore » nerve, which is associated with typical visual field defects. In 1992, the World Health Organization estimated that, in the global population, 5.2 million people were blind as a result of glaucoma, making it the third leading cause of blindness worldwide. The most common form is adult-onset primary open-angle glaucoma, which represents {ge}50% of all cases of glaucoma. Among Caucasians, this form of the disorder affects {approximately}2% of the population >45 years old. In African Americans, prevalence of adult-onset open-angle glaucoma is three to four times higher than that observed in White Americans. More than 15 million North Americans may have some form of glaucoma, but at least half of them may not be aware of it. 43 refs., 1 tab.« less

  12. The usefulness of CorvisST Tonometry and the Ocular Response Analyzer to assess the progression of glaucoma

    NASA Astrophysics Data System (ADS)

    Matsuura, Masato; Hirasawa, Kazunori; Murata, Hiroshi; Nakakura, Shunsuke; Kiuchi, Yoshiaki; Asaoka, Ryo

    2017-01-01

    Corneal Visualization Scheimpflug Technology (CST) and Ocular Response Analyzer (ORA) measurements were carried out in 105 eyes of 69 patients with primary open-angle glaucoma. All patients had axial length (AL), central corneal thickness (CCT), intraocular pressure (IOP) with Goldmann applanation tonometry (GAT) and eight visual fields (VF)s with the Humphrey Field Analyzer. VF progression was summarized using a time trend analysis of mean total deviation (mTD) and the association between mTD progression rate and a number of ocular parameters (including CST and ORA measurements) was assessed using mixed linear regression analysis. The optimal model of VF progression selected based on the corrected Akaike Information Criteria (AICc) included ORA’s corneal hysteresis (CH) parameter as well as a number of CST measurements: mTD progression rate = 1.2-0.070 * mean GAT + 0.090 * CH-1.5 * highest concavity deformation amplitude with CST + 9.4 * A1 deformation amplitude with CST-0.05 * A2 length with CST (AICc = 125.8). Eyes with corneas that experience deep indentation at the maximum deformation, shallow indentation at the first applanation and wide indentation at the second applanation in the CST measurement are more likely to experience faster rates of VF progression.

  13. Prediction of Curve Progression in Idiopathic Scoliosis: Validation of the Sanders Skeletal Maturity Staging System.

    PubMed

    Sitoula, Prakash; Verma, Kushagra; Holmes, Laurens; Gabos, Peter G; Sanders, James O; Yorgova, Petya; Neiss, Geraldine; Rogers, Kenneth; Shah, Suken A

    2015-07-01

    Retrospective case series. This study aimed to validate the Sanders Skeletal Maturity Staging System and to assess its correlation to curve progression in idiopathic scoliosis. The Sanders Skeletal Maturity Staging System has been used to predict curve progression in idiopathic scoliosis. This study intended to validate that initial study with a larger sample size. We retrospectively reviewed 1100 consecutive patients with idiopathic scoliosis between 2005 and 2011. Girls aged 8 to 14 years (<2 yr postmenarche) and boys aged 10 to 16 years who had obtained at least 1 hand and spine radiograph on the same day for evaluation of skeletal age and scoliosis curve magnitude were followed to skeletal maturity (Risser stage 5 or fully capped Risser stage 4), curve progression to 50° or greater, or spinal fusion. Patients with nonidiopathic curves were excluded. There were 161 patients: 131 girls (12.3 ± 1.2 yr) and 30 boys (13.9 ± 1.1 yr). The distribution of patients within Sanders stage (SS) 1 through 7 was 7, 28, 41, 45, 7, 31, and 2 patients, respectively; modified Lenke curve types 1 to 6 were 26, 12, 63, 5, 38, and 17 patients, respectively. All patients in SS2 with initial Cobb angles of 25° or greater progressed, and patients in SS1 and SS3 with initial Cobb angles of 35° or greater progressed. Similarly, all patients with initial Cobb angles of 40° or greater progressed except those in SS7. Conversely, none of the patients with initial Cobb angles of 15° or less or those in SS5, SS6, and SS7 with initial Cobb angles of 30° or less progressed. Predictive progression of 67%, 50%, 43%, 27%, and 60% was observed for subgroups SS1/30°, SS2/20°, SS3/30°, SS4/30°, and SS6/35° respectively. This larger cohort shows a strong predictive correlation between SS and initial Cobb angle for probability of curve progression in idiopathic scoliosis. 3.

  14. [Magnetotherapy designed to affect cervical sympathetic ganglia for the treatment of patients with primary open-angle glaucoma].

    PubMed

    Veselova, E V; Kamenskikh, T G; Raĭgorodkiĭ, Iu M; Kolbenev, I O; Myshkina, E S

    2010-01-01

    The traveling magnetic field was used to treat primary open-angle glaucoma. The field was applied to the projection of cervical sympathetic ganglia of the patients. Hemodynamic parameters of posterior short ciliary arteries and central retinal artery were analysed along with visual evoked potentials, visual field limits, and visual acuity. It was shown that magnetotherapy with the use of an AMO-ATOS apparatus produces better clinical results in patients with stage I and II primary open-angle glaucoma compared with medicamentous therapy (intake of trental tablets).

  15. Evidence-based practice guideline of Chinese herbal medicine for primary open-angle glaucoma (qingfeng -neizhang).

    PubMed

    Yang, Yingxin; Ma, Qiu-Yan; Yang, Yue; He, Yu-Peng; Ma, Chao-Ting; Li, Qiang; Jin, Ming; Chen, Wei

    2018-03-01

    Primary open angle glaucoma (POAG) is a chronic, progressive optic neuropathy. The aim was to develop an evidence-based clinical practice guideline of Chinese herbal medicine (CHM) for POAG with focus on Chinese medicine pattern differentiation and treatment as well as approved herbal proprietary medicine. The guideline development group involved in various pieces of expertise in contents and methods. Authors searched electronic databases include CNKI, VIP, Sino-Med, Wanfang data, PubMed, the Cochrane Library, EMBASE, as well as checked China State Food and Drug Administration (SFDA) from the inception of these databases to June 30, 2015. Systematic reviews and randomized controlled trials of Chinese herbal medicine treating adults with POAG were evaluated. Risk of bias tool in the Cochrane Handbook and evidence strength developed by the GRADE group were applied for the evaluation, and recommendations were based on the findings incorporating evidence strength. After several rounds of Expert consensus, the final guideline was endorsed by relevant professional committees. CHM treatment principle and formulae based on pattern differentiation together with approved patent herbal medicines are the main treatments for POAG, and the diagnosis and treatment focusing on blood related patterns is the major domain. CHM therapy alone or combined with other conventional treatment reported in clinical studies together with Expert consensus were recommended for clinical practice.

  16. High prevalence of narrow angles among Chinese-American glaucoma and glaucoma suspect patients.

    PubMed

    Seider, Michael I; Pekmezci, Melike; Han, Ying; Sandhu, Simi; Kwok, Shiu Y; Lee, Roland Y; Lin, Shan C

    2009-01-01

    To evaluate the prevalence of gonioscopically narrow angles in a Chinese-American population with glaucoma or glaucoma suspicion. Charts from all Chinese-American patients seen in a comprehensive ophthalmology clinic in the Chinatown district of San Francisco in 2002 were reviewed. One eye from each patient with glaucoma or glaucoma suspicion that met inclusion criteria was included (n=108). Data were collected for sex, age, race (self-declared), refraction (spherical equivalent), intraocular pressure, gonioscopy, and vertical cup-to-disk ratio. Sixty percent (n=65) of Chinese-American eyes with glaucoma or glaucoma suspicion had gonioscopically narrow angles (Shaffer grade < or = 2 in 3 or more quadrants). Those with narrow angles were significantly older (P=0.004) than their open angle counterparts, but the 2 groups did not differ in terms of sex, refraction, intraocular pressure, or cup-to-disk ratio (all, P > or = 0.071). In a multivariate model including age, sex, and refraction as predictors of angle grade (open or narrow), only age was a significant predictor of angle grade (P=0.004). A large proportion of Chinese-Americans in our study population with glaucoma or glaucoma suspicion had gonioscopically narrow angles. In multivariate analysis, patients with narrow angles were older than those with open angles but did not differ from them in terms of sex or refraction. Continued evaluation of angle closure glaucoma risk among Chinese-Americans is needed.

  17. Adjuvant effect of Chakshushya Rasayana with beta-blocker eye drops in the management of progressive glaucomatous optic neuropathy: An open-label randomized controlled trial.

    PubMed

    Dhiman, K S; Adhoor, Veeranagouda S; Agarwal, Riju; Mehta, Amit J

    2016-01-01

    Primary open angle glaucoma is an insidious and chronic vision-threatening eye ailment due to neuro-retino-optic nerve degeneration, which may be due to the raised intraocular pressure (IOP) or due to independent factors. Management of glaucoma is mainly concentrated on lowering IOP that requires lifetime topical medication, different ocular medicaments for lowering of IOP, and surgical interventions, but it has its own limitations to control the progression of glaucomatous optic neuropathy (GON), and this is the reason behind the use of alternative neuroprotective adjuvants. To evaluate the neuroprotective effect of Ayurvedic line of management of progressive GON. Ingredients of trial drug Vara Fort powder ( Chakshushya Rasayana ) were procured from the Institute Pharmacy, except Swarnamakshika Bhasma , which was purchased from Dhootapapeshwar Pharmaceuticals. The patients fulfilling inclusion criteria, attending outpatient and inpatient departments, irrespective of their sex, race, religion, occupation, etc., were selected and divided into two groups with open-labeled randomization. In Group A, in addition to betaxolol (0.1%) or timolol (0.5%) (non-iobrim), Chakshushya Rasayana 6 g/day orally with Triphala Ghrita and honey along with Koshtha-Shuddhi (body-microchannel clearing treatment) protocol was tried. Nasya (oleation through nasal route) with Jeevantyadi Taila and Tarpana (eye satiation) with Go-Ghrita were also performed. In Group B (control), brimonidine (iobrim) 0.2% eye drop was used for 3 months. Significant improvement was observed in subjective parameters in Group A such as blurred vision, frequent change of presbyopic glasses, and delayed dark adaptation. Chakshushya Rasayana , if administered in a systematic approach along with a modern topical betaxolol or timolol eye drops, has a definite role in improving the lost retinal sensitivity as much as up to 12 dB in 3 months duration.

  18. Assessment of morphological and anatomical characteristics of mental foramen using cone beam computed tomography.

    PubMed

    Goyushov, Samir; Tözüm, Melek Didem; Tözüm, Tolga Fikret

    2018-05-25

    To determine the shape, position, vertical height, surrounding bone characteristics, and opening angle of mental foramen (MF) using dental cone beam computed tomography (CBCT). A retrospective study was performed on 663 patients. CBCT records analyzed for the shape, position, and surrounding bone measurements of the MF using Simplant 3D software (Hasselt, Belgium). Opening angle of MF was also assessed. Kruskal-Wallis and Mann-Whitney U tests were employed to test significant differences between parameters, genders and ages. All mental foramina were visualized. Regarding location, 49.2% of the MFs were located between first and second premolars, 7.7 distal and 39.7% coincident to the apex of the mandibular second premolar. The mean MF opening angle was 45.4° on the right side, and 45.9° on the left. There were no statistically differences between gender groups with regard to the opening angle degrees. This study may provide useful information about variations in the position, shape and size, angle of mental foramen, which may help the practitioners to perform safer mental nerve blocks and surgical procedures.

  19. Case report: imaging and treatment of ophthalmic manifestations in oculodentodigital dysplasia.

    PubMed

    Mosaed, Sameh; Jacobsen, Bradley H; Lin, Ken Young

    2016-01-07

    Diagnostic and surgical management of severe chronic angle- closure glaucoma secondary to ciliary body cysts can be difficult to manage in a patient with oculodentodigital dysplasia. A 6-year old girl with oculodentodigital dysplasia, with progressive chronic angle- closure glaucoma secondary to ciliary body cysts presented to our clinic. The initial examination revealed counting fingers vision in the left eye. Intraocular pressure (IOP), as assessed by tonopen, was 31 mm Hg. Ultrasound biomicroscopy revealed ciliary body cysts in the left eye, and gonioscopy confirmed chronic angle closure. A tube shunt was placed to control the elevated IOP. A year after her tube shunt placement in the left eye, ultrasound biomiscropy was performed on her right eye and showed no ciliary body cysts. Gonioscopy in the right eye revealed an open angle to the ciliary body band. Subsequent serial gonioscopy every 3 months showed gradual narrowing of the right eye angle and finally three-and-a-half years after tube placement of the left eye, her right eye IOP became uncontrolled with medications alone and a tube shunt was similarly placed in the right eye. Intraoperative ultrasound biomicroscopy performed at the time of the right eye tube shunt revealed extensive ciliary body cysts in the right eye. Her IOP in both eyes have been well controlled since the placement of tube shunts. This is one of the first reported cases of severe chronic angle- closure glaucoma secondary to ciliary body cysts in a patient with oculodentodigital dysplasia. We believe that early screening for ciliary body cysts is important in patients with oculodentodigital dysplasia.

  20. Agreement between Gonioscopic Examination and Swept Source Fourier Domain Anterior Segment Optical Coherence Tomography Imaging

    PubMed Central

    Nguyen, Donna; Minnal, Vandana R.

    2016-01-01

    Purpose. To evaluate interobserver, intervisit, and interinstrument agreements for gonioscopy and Fourier domain anterior segment optical coherence tomography (FD ASOCT) for classifying open and narrow angle eyes. Methods. Eighty-six eyes with open or narrow anterior chamber angles were included. The superior angle was classified open or narrow by 2 of 5 glaucoma specialists using gonioscopy and imaged by FD ASOCT in the dark. The superior angle of each FD ASOCT image was graded as open or narrow by 2 masked readers. The same procedures were repeated within 6 months. Kappas for interobserver and intervisit agreements for each instrument and interinstrument agreements were calculated. Results. The mean age was 50.9 (±18.4) years. Interobserver agreements were moderate to good for both gonioscopy (0.57 and 0.69) and FD ASOCT (0.58 and 0.75). Intervisit agreements were moderate to excellent for both gonioscopy (0.53 to 0.86) and FD ASOCT (0.57 and 0.85). Interinstrument agreements were fair to good (0.34 to 0.63), with FD ASOCT classifying more angles as narrow than gonioscopy. Conclusions. Both gonioscopy and FD ASOCT examiners were internally consistent with similar interobserver and intervisit agreements for angle classification. Agreement between instruments was fair to good, with FD ASOCT classifying more angles as narrow than gonioscopy. PMID:27990300

  1. Transition paths of Met-enkephalin from Markov state modeling of a molecular dynamics trajectory.

    PubMed

    Banerjee, Rahul; Cukier, Robert I

    2014-03-20

    Conformational states and their interconversion pathways of the zwitterionic form of the pentapeptide Met-enkephalin (MetEnk) are identified. An explicit solvent molecular dynamics (MD) trajectory is used to construct a Markov state model (MSM) based on dihedral space clustering of the trajectory, and transition path theory (TPT) is applied to identify pathways between open and closed conformers. In the MD trajectory, only four of the eight backbone dihedrals exhibit bistable behavior. Defining a conformer as the string XXXX with X = "+" or "-" denoting, respectively, positive or negative values of a given dihedral angle and obtaining the populations of these conformers shows that only four conformers are highly populated, implying a strong correlation among these dihedrals. Clustering in dihedral space to construct the MSM finds the same four bistable dihedral angles. These state populations are very similar to those found directly from the MD trajectory. TPT is used to obtain pathways, parametrized by committor values, in dihedral state space that are followed in transitioning from closed to open states. Pathway costs are estimated by introducing a kinetics-based procedure that orders pathways from least (shortest) to greater cost paths. The least costly pathways in dihedral space are found to only involve the same XXXX set of dihedral angles, and the conformers accessed in the closed to open transition pathways are identified. For these major pathways, a correlation between reaction path progress (committors) and the end-to-end distance is identified. A dihedral space principal component analysis of the MD trajectory shows that the first three modes capture most of the overall fluctuation, and pick out the same four dihedrals having essentially all the weight in those modes. A MSM based on root-mean-square backbone clustering was also carried out, with good agreement found with dihedral clustering for the static information, but with results that differ significantly for the pathway analysis.

  2. Glaucoma anterior chamber morphometry based on optical Scheimpflug images.

    PubMed

    Alonso, Ruiz Simonato; Ambrósio Junior, Renato; Paranhos Junior, Augusto; Sakata, Lisandro Massanori; Ventura, Marcelo Palis

    2010-01-01

    To compare the performance of gonioscopy and noncontact morphometry with anterior chamber tomography (High Resolution Pentacam - HR) using optical Scheimpflug images in the evaluation of the anterior chamber angle (ACA). Transversal study. 112 eyes from 74 subjects evaluated at the Glaucoma Department, Fluminense Federal University, underwent gonioscopy and Pentacam HR. Using gonioscopy, the ACA was graded using the Shaffer Classification (SC) by a single experienced examiner masked to the Pentacam HR findings. Narrow angle was determined in eyes in which the posterior trabecular meshwork could not be seen in two or more quadrants on non-indentation gonioscopy (SC Grade 2 or less). Pentacam HR images of the nasal and temporal quadrants were evaluated by custom software to automatically obtain anterior chamber measurements, such as: anterior chamber angle (ACA), anterior chamber volume (ACV) and anterior chamber depth (ACD). Based on gonioscopy results, 74 (60.07%) eyes of patients classified as open-angle (SC 3 and 4) and 38 (33.93%) eyes of patients classified as narrow-angle (SC 1 and 2). Noncontact morphometry with Scheimpflug images revealed a mean ACA of 39.20 ± 5.31 degrees for open-angle and 21.18 ± 7.98 degrees for narrow-angle. The open-angle group showed significant greater ACV and ACD values when compared to narrow-angle group (ACV of 193 ± 36 mm³ vs. 90 ± 25 mm³, respectively, p<0.001; and ACD of 3,09 ± 0,42 mm vs. 1,55 ± 0,64 mm, respectively, p<0.0001.). In screening eyes with open-angle and narrow-angle with the Pentacam ACA of 20º (SC Grade 2) using the ROC curves, the analysis showed 52.6% of sensitivity and 100% of specificity. The Pentacam showed ability in detecting eyes at risk for angle closure analyzing ACV and ACD.

  3. Peripapillary schisis in open-angle glaucoma.

    PubMed

    Dhingra, N; Manoharan, R; Gill, S; Nagar, M

    2017-03-01

    PurposeTo report clinical features, topographic findings and outcome of 10 eyes with peripapillary schisis in open-angle glaucoma.Patients and methodsA retrospective review of patients with open-angle glaucoma who were noted to have peripapillary schisis on optical coherence tomography (OCT) were included. Serial peripapillary and macula infrared and OCT images, visual acuity, visual fields, and schisis appearance were reviewed.ResultsTen eyes of nine patients with open-angle glaucoma were detected to have the presence of peripapillary schisis. Nerve fibre layer schisis was detected in all eyes and one eye had an associated macular schisis. None of the eyes had an acquired pit of the optic nerve or pathological myopia. The mean intraocular pressures at detection was 18.3±4.3 mm Hg and the schisis resolved in four eyes after a mean follow-up of 21.2±8.8 months. Visual field worsening was noted in 4 of the 10 eyes and the resolution of schisis resulted in significant reduction in the retinal nerve fibre layer (RNFL) thickness.ConclusionsPeripapillary schisis detected during the normal course of open-angle glaucoma can resolve spontaneously and rarely involves the macula. Its resolution leads to reduction in RNFL thickness; therefore, caution is advised while interpreting serial scans.

  4. Assessment of narrow angles by gonioscopy, Van Herick method and anterior segment optical coherence tomography.

    PubMed

    Park, Seong Bae; Sung, Kyung Rim; Kang, Sung Yung; Jo, Jung Woo; Lee, Kyoung Sub; Kook, Michael S

    2011-07-01

    To evaluate anterior chamber (AC) angles using gonioscopy, Van Herick technique and anterior segment optical coherence tomography (AS-OCT). One hundred forty-eight consecutive subjects were enrolled. The agreement between any two of three diagnostic methods, gonioscopy, AS-OCT and Van Herick, was calculated in narrow-angle patients. The area under receiver-operating characteristic curves (AUC) for discriminating between narrow and open angles determined by gonioscopy was calculated in all participants for AS-OCT parameter angle opening distance (AOD), angle recess area, trabecular iris surface area and anterior chamber depth (ACD). As a subgroup analysis, capability of AS-OCT parameters for detecting angle closure defined by AS-OCT was assessed in narrow-angle patients. The agreement between the Van Herick method and gonioscopy in detecting angle closure was excellent in narrow angles (κ = 0.80, temporal; κ = 0.82, nasal). However, agreement between gonioscopy and AS-OCT and between the Van Herick method and AS-OCT was poor (κ = 0.11-0.16). Discrimination capability of AS-OCT parameters between open and narrow angles determined by gonioscopy was excellent for all AS-OCT parameters (AUC, temporal: AOD500 = 0.96, nasal: AOD500 = 0.99). The AUCs for detecting angle closure defined by AS-OCT image in narrow angle subjects was good for all AS-OCT parameters (AUC, 0.80-0.94) except for ACD (temporal: ACD = 0.70, nasal: ACD = 0.63). Assessment of narrow angles by gonioscopy and the Van Herick technique showed good agreement, but both measurements revealed poor agreement with AS-OCT. The angle closure detection capability of AS-OCT parameters was excellent; however, it was slightly lower in ACD.

  5. Recent Progress in the Study of Inorganic Nanotubes and Fullerene-Like Structures

    NASA Astrophysics Data System (ADS)

    Tenne, R.; Seifert, G.

    2009-08-01

    The synthesis of WS2 inorganic nanotubes (INT) and inorganic fullerene-like (IF) structures in 1992 signified the opening of a fertile and challenging field of scientific endeavor. These structures were the first of a long and ever-expanding series of INT and IF structures. Although initially much of the effort concentrated on the synthesis of INT and IF from compounds with layered structures, recently there has been a surge of efforts to synthesize crystalline and polycrystalline nanotubular structures from compounds with quasi-isotropic structures, like spinels, BaTiO3, SiO2, TiO2, and many others. The present review summarizes some of the progress in this field in recent years. Much of the progress in this field was achieved through strong interaction between theoretical and experimental work. This article has four themes: (a) new synthetic approaches leading to new kinds of IF and INT; (b) study of the molecular structure of such nanoparticles with new tools, such as aberration-corrected transmission electron microscopy (TEM) and high-angle annular dark field (HAADF); (c) recent progress in the investigation of the properties of such nanostructures; and (d) examples of applications for which clear progress has been accomplished, in particular in solid lubrication and high-strength nanocomposites.

  6. High Prevalence of Narrow Angles among Chinese-American Glaucoma and Glaucoma Suspect Patients

    PubMed Central

    Seider, Michael I; Pekmezci, Melike; Han, Ying; Sandhu, Simi; Kwok, Shiu Y; Lee, Roland Y; Lin, Shan C

    2009-01-01

    Purpose To evaluate the prevalence of gonioscopically narrow angles in a Chinese-American population with glaucoma or glaucoma suspicion. Patients and Methods Charts from all Chinese-American patients seen in a comprehensive ophthalmology clinic in the Chinatown district of San Francisco in 2002 were reviewed. One eye from each patient with glaucoma or glaucoma suspicion that met inclusion criteria was included (n=108). Data was collected for gender, age, race (self-declared), refraction (spherical equivalent), intraocular pressure (IOP), gonioscopy and vertical cup-to-disk ratio (CDR). Results Sixty percent (n=65) of Chinese-American eyes with glaucoma or glaucoma suspicion had gonioscopically narrow angles (Shaffer grade ≤2 in three or more quadrants). Those with narrow angles were significantly older (P=0.004) than their open angle counterparts, but the two groups did not differ in terms of gender, refraction, IOP or CDR (all, P≥0.071). In a multivariate model including age, gender and refraction as predictors of angle grade (open or narrow), only age was a significant predictor of angle grade (P=0.004). Conclusions A large proportion of Chinese-Americans in our study population with glaucoma or glaucoma suspicion had gonioscopically narrow angles. In multivariate analysis, patients with narrow angles were older than those with open angles but did not differ from them in terms of gender or refraction. Continued evaluation of angle closure glaucoma risk among Chinese-Americans is needed. PMID:19826385

  7. Comparison of a technique using a new percutaneous osteosynthesis device with conventional open surgery for displaced patella fractures in a randomized controlled trial.

    PubMed

    Luna-Pizarro, Daniel; Amato, Dante; Arellano, Francisco; Hernández, Armando; López-Rojas, Pablo

    2006-09-01

    To compare the percutaneous patellar osteosynthesis system (PPOS) technique with open surgery for patella fractures. Randomized controlled trial. Referral orthopedic and trauma center. Fifty-three patients with displaced patellar fractures. Stabilization and fixation of patellar fractures with PPOS or open surgery. Knee-flexion and -extension angles, pain, surgical time, and assessment of knee function based on the Knee Society Clinical Rating Scale (KSCRS). Comparison of PPOS and open-surgery groups at 4 weeks showed the following: pain, 3.7 +/- 1.6 versus 6.2 +/- 1.4 arbitrary units, P < 0.001; flexion angle, 46 +/- 20.7 versus 12.7 +/- 6.0 degrees, P < 0.001; extension angle, -2.5 versus -3.8 degrees, P < 0.001. At 8 weeks, the following was demonstrated: pain, 1.3 +/- 1.6 versus 4.1 +/- 2.1 arbitrary units, P < 0.001; flexion angle, 87 +/- 17.3 versus 34 +/- 26 degrees, P < 0.001; extension angle, 0 versus -3 degrees, P < 0.001. Surgical time was 35.3 +/- 7.8 versus 66.2 +/- 14.1 minutes, P < 0.001. KSCRS assessment was 84 +/- 4 versus 70 +/- 8, P < 0.001 at 8 weeks; 85 +/- 2 versus 73 +/- 8, P < 0.001 at 12 months; and 85 +/- 1 versus 82 +/- 7, P = 0.246 at 24 months. Frequency of total complications (infections, fragment displacement, and wire-related pain) was significantly lower in the PPOS than in the open-surgery group (P < 0.02). PPOS for patella fractures was associated with shorter surgical time, less pain, better mobility angles, higher functional score up to 2 years, and a lower incidence of complications than open surgery.

  8. Regional distribution of circumferential residual strains in the human aorta according to age and gender.

    PubMed

    Sokolis, Dimitrios P; Savva, Giannis D; Papadodima, Stavroula A; Kourkoulis, Stavros K

    2017-03-01

    The biomechanical response of the human aorta varies with axial location, but little is known about the respective variation of residual strains. Such data are available for common lab animals, but in the traditional opening angle measurement the aorta is considered as an ideal cylinder and average residual strains are measured, so that the spatial variations of local residual strains are not determined. The present study provides opening angle and residual strain data throughout the course and around the circumference of the aorta harvested during autopsy. Opening angle showed notable topographical variation; the highest value was at the top of aortic arch, declining abruptly toward the ascending aorta and to a near-constant value in the descending aorta, and rising in the abdominal aorta. The variation of curvature and of external but not internal residual stretch resembled that of opening angle. Extensive residual stress and wall thickness differences were evidenced among quadrants, with the more pre-stressed being also the thicker quadrants. Gender had overall minor effects, but aging led to increased parameters, occurring earlier in the distal aorta but at later stages becoming predominant proximally. Differences in caliber were pronounced in older subjects, unlike those in opening angle, residual stretches, and thickness that were striking in middle-aged subjects. By contrast, curvature decreased with aging in relation to the smaller percentwise opening angle differences. Detailed knowledge of the zero-stress/no-load geometry of the human aortic wall is critical for an in-depth understanding of aortic physiology, while providing the basis for comparison with disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Gonioscopy-assisted Transluminal Trabeculotomy: An Ab Interno Circumferential Trabeculotomy: 24 Months Follow-up.

    PubMed

    Grover, Davinder S; Smith, Oluwatosin; Fellman, Ronald L; Godfrey, David G; Gupta, Aditi; Montes de Oca, Ildamaris; Feuer, William J

    2018-05-01

    The purpose of this study was to provide 24-month follow-up on surgical success and safety of an ab interno circumferential 360-degree trabeculotomy. Chart review of patients who underwent a gonioscopy-assisted transluminal trabeculotomy (GATT) procedure was performed by 4 of the authors (D.S.G., O.S., R.L.F., and D.G.G.). The surgery was performed in adults with various types of open-angle glaucoma with preoperative intraocular pressures (IOPs) of ≥18 mm Hg. In total, 198 patients aged 24 to 89 years underwent the GATT procedure with at least 18 months follow-up. Patients with primary open-angle glaucoma had an average IOP decrease of 9.2 mm Hg at 24 months with an average decrease of 1.43 glaucoma medications. The mean percentage of IOP decrease in these primary open-angle glaucoma groups at 24 months was 37.3%. In secondary open-angle glaucoma, at 24 months there was an average decrease in IOP of 14.1 mm Hg on an average of 2.0 fewer medications. The mean percentage of IOP decrease in the secondary open-angle glaucoma groups at 24 months was 49.8%. The cumulative proportion of failure at 24 months ranged from 0.18 to 0.48, depending on the group. In all 6 study groups, at all 5 postoperative time points (3, 6, 12, 18, and 24 mo) the mean IOP and reduction in glaucoma medications was significantly reduced from baseline (P<0.001) with the exception of one time point. The 24-month results demonstrate that GATT is relatively safe and effective in treating various forms of open-angle glaucoma. The long-term results for GATT are relatively equivalent to those previously reported for GATT and ab externo trabeculotomy studies.

  10. Structural characteristics of the acquired optic disc pit and the rate of progressive retinal nerve fiber layer thinning in primary open-angle glaucoma.

    PubMed

    Lee, Seung Hyen; Lee, Eun Ji; Kim, Tae-Woo

    2015-10-01

    The optic disc pit (ODP) has been considered a region of localized susceptibility to the damage of glaucoma. To determine whether the rate of retinal nerve fiber layer (RNFL) thinning differs according to the presence and structural characteristics of an ODP in primary open-angle glaucoma. We performed a prospective case-control study that included 163 eyes with primary open-angle glaucoma (83 with an ODP and 80 without an ODP) from Glaucoma Clinic of Seoul National University Bundang Hospital. Participants were enrolled from the ongoing Investigating Glaucoma Progression Study from January 1, 2012, through May 31, 2014. Mean (SD) follow-up was 3.32 (0.49) years (through May 31, 2014). Optic nerve heads underwent swept-source optical coherence tomography (OCT) to determine the presence of focal lamina cribrosa alteration and its structural characteristics. Eyes with and without photographic ODPs and corresponding microscopic laminar alterations were assigned to the ODP and non-ODP groups, respectively. The rates of progressive thinning of global and 6 sectoral spectral-domain OCT RNFL thicknesses were determined by linear regression and compared between the 2 groups. We used a general linear model to determine the factors associated with the rate of RNFL thinning; data obtained from September 21, 2009, through May 31, 2014, were used to calculate the rate of RNFL thinning. The relationship between the presence and structural characteristics of ODPs and the rate of progressive OCT RNFL thinning. Thinning of the RNFL was faster in the ODP group than in the non-ODP group in the global (mean [SD], -1.44 [1.31] vs -0.93 [1.10] [95% CI, -0.97 to -0.19] μm/y; P = .008), temporoinferior (mean [SD], -4.17 [4.15] vs -1.97 [3.26] [95% CI, -3.36 to -1.04] μm/y; P < .001), and temporal (mean [SD], -1.92 [2.62] vs -0.89 [1.62] [95% CI, -1.70 to -0.35] μm/y; P = .003) sectors. The rate of RNFL thinning was maximum in the temporoinferior sector (mean [SD], -4.17 [4.15] μm/y) and corresponded to the frequency distribution of ODPs. Regression analysis revealed that faster global RNFL thinning was related to a higher untreated intraocular pressure (β = -0.07; 95% CI, -0.11 to -0.03; P = .001), episodes of disc hemorrhage (β = -0.74; 95% CI, -1.79 to 0.31; P = .003), the presence of β-zone parapapillary atrophy (β = -0.47; 95% CI, -1.13 to 0.20; P = .02), and the presence of ODPs (β = -0.41; 95% CI, -1.14 to 0.32; P = .02). The maximum rate of RNFL thinning was associated with higher untreated intraocular pressure (β = -0.24; 95% CI, -0.35 to -0.13; P < .001), disc hemorrhage (β = -1.54; 95% CI, -2.88 to -0.19; P < .001), and the presence (β = -1.04; 95% CI, -2.14 to 0.07; P = .004), far-peripheral location (β = -1.75; 95% CI, -3.05 to -0.46; P = .008), and partial-thickness depth (β = -1.45; 95% CI, -2.75 to -0.16; P = .03) of an ODP. The presence and structural characteristics of ODPs were associated with global and focal progression as assessed by the rate of OCT RNFL thinning. The assessment of ODP structure using swept-source OCT may help to predict the location of future progression.

  11. The Frequency of Optical Coherence Tomography Testing in Glaucoma at a Single Academic Medical Center.

    PubMed

    Griffith, Joseph F; Goldberg, Jeffrey L

    2016-03-01

    To determine the frequency of optical coherence tomography (OCT) examinations compared with clinical examinations and visual field (VF) tests in patients with 5 types of glaucoma. A retrospective, longitudinal cohort study was conducted of 5154 patients treated between 2003 and 2010 at a single academic medical center. Patients were classified using billing records as having primary open-angle glaucoma, low-tension open-angle glaucoma (NTG), pigmentary open-angle glaucoma, chronic angle-closure glaucoma, or pseudoexfoliation glaucoma. Analysis of variance, χ test, and exact χ test were performed to identify associations between glaucoma type and test frequency. Pigmentary open-angle glaucoma and NTG patients had a higher rate of undergoing at least 2 VFs (94.4%, 94.9%), and chronic angle-closure glaucoma patients had a lower rate of undergoing at least 2 OCTs (25.3%) than all other glaucoma types. NTG patients also had the highest rate of undergoing at least 2 OCTs and at least 2 VFs (36.6%). Overall, the rate of clinical examinations (2.68 examinations/y) exceeded the rates of OCTs (1.39 examinations/y), which exceeded the rate of VF tests (1.24 tests/y). There were no differences in OCT frequency between glaucoma types (0.91 to 1.63 OCTs/y). Within each glaucoma diagnosis, patients had clinical examinations more frequently than OCTs and clinical examinations more frequently than VFs. Primary open-angle glaucoma and pseudoexfoliation glaucoma patients also had OCTs more frequently than VFs. More patients had at least 2 VF tests than at least 2 OCTs (4481 vs. 1679). The relative use of clinical examinations, VF testing, and OCT imaging varies among glaucoma diagnoses.

  12. Developing new automated alternation flicker using optic disc photography for the detection of glaucoma progression

    PubMed Central

    Ahn, J; Yun, I S; Yoo, H G; Choi, J-J; Lee, M

    2017-01-01

    Purpose To evaluate a progression-detecting algorithm for a new automated matched alternation flicker (AMAF) in glaucoma patients. Methods Open-angle glaucoma patients with a baseline mean deviation of visual field (VF) test>−6 dB were included in this longitudinal and retrospective study. Functional progression was detected by two VF progression criteria and structural progression by both AMAF and conventional comparison methods using optic disc and retinal nerve fiber layer (RNFL) photography. Progression-detecting performances of AMAF and the conventional method were evaluated by an agreement between functional and structural progression criteria. RNFL thickness changes measured by optical coherence tomography (OCT) were compared between progressing and stable eyes determined by each method. Results Among 103 eyes, 47 (45.6%), 21 (20.4%), and 32 (31.1%) eyes were evaluated as glaucoma progression using AMAF, the conventional method, and guided progression analysis (GPA) of the VF test, respectively. The AMAF showed better agreement than the conventional method, using GPA of the VF test (κ=0.337; P<0.001 and κ=0.124; P=0.191, respectively). The rates of RNFL thickness decay using OCT were significantly different between the progressing and stable eyes when progression was determined by AMAF (−3.49±2.86 μm per year vs −1.83±3.22 μm per year; P=0.007) but not by the conventional method (−3.24±2.42 μm per year vs −2.42±3.33 μm per year; P=0.290). Conclusions The AMAF was better than the conventional comparison method in discriminating structural changes during glaucoma progression, and showed a moderate agreement with functional progression criteria. PMID:27662466

  13. Faint Object Camera imaging and spectroscopy of NGC 4151

    NASA Technical Reports Server (NTRS)

    Boksenberg, A.; Catchpole, R. M.; Macchetto, F.; Albrecht, R.; Barbieri, C.; Blades, J. C.; Crane, P.; Deharveng, J. M.; Disney, M. J.; Jakobsen, P.

    1995-01-01

    We describe ultraviolet and optical imaging and spectroscopy within the central few arcseconds of the Seyfert galaxy NGC 4151, obtained with the Faint Object Camera on the Hubble Space Telescope. A narrowband image including (O III) lambda(5007) shows a bright nucleus centered on a complex biconical structure having apparent opening angle approximately 65 deg and axis at a position angle along 65 deg-245 deg; images in bands including Lyman-alpha and C IV lambda(1550) and in the optical continuum near 5500 A, show only the bright nucleus. In an off-nuclear optical long-slit spectrum we find a high and a low radial velocity component within the narrow emission lines. We identify the low-velocity component with the bright, extended, knotty structure within the cones, and the high-velocity component with more confined diffuse emission. Also present are strong continuum emission and broad Balmer emission line components, which we attribute to the extended point spread function arising from the intense nuclear emission. Adopting the geometry pointed out by Pedlar et al. (1993) to explain the observed misalignment of the radio jets and the main optical structure we model an ionizing radiation bicone, originating within a galactic disk, with apex at the active nucleus and axis centered on the extended radio jets. We confirm that through density bounding the gross spatial structure of the emission line region can be reproduced with a wide opening angle that includes the line of sight, consistent with the presence of a simple opaque torus allowing direct view of the nucleus. In particular, our modelling reproduces the observed decrease in position angle with distance from the nucleus, progressing initially from the direction of the extended radio jet, through our optical structure, and on to the extended narrow-line region. We explore the kinematics of the narrow-line low- and high-velocity components on the basis of our spectroscopy and adopted model structure.

  14. Radiographic comparison of surgical hip dislocation and hip arthroscopy for treatment of cam deformity in femoroacetabular impingement.

    PubMed

    Bedi, Asheesh; Zaltz, Ira; De La Torre, Katrina; Kelly, Bryan T

    2011-07-01

    Whether open or arthroscopic techniques are employed, the goal of femoroacetabular impingement (FAI) surgery is to achieve impingement-free range of motion. While arthroscopic approaches have improved and gained popularity, an objective evaluation of the surgical correction achieved with this approach compared with open surgery remains to be defined in the literature. This study was undertaken to compare the efficacy of arthroscopic osteoplasty and open surgical dislocation in treating FAI dysmorphology in a consecutive series of patients. Cohort study; Level of evidence, 3. Surgical treatment was performed in 60 male patients under 40 years of age for symptomatic FAI refractory to nonoperative management. Patients were matched (not randomized) to treatment groups: 30 patients (15 left and 15 right hips) underwent arthroscopic cam and/or rim osteoplasty with labral debridement and/or refixation by an arthroscopic surgeon; and 30 (14 left and 16 right hips) underwent open surgical dislocation, cam and/or rim osteoplasty, and labral debridement or refixation by a hip preservation surgeon. Anteroposterior (AP) pelvis and extended-neck (Dunn) lateral radiographs were obtained and the depth of resection and arc of resection were measured by assessment of anterior femoral head-neck offset, AP and lateral α angle, and β angle on preoperative and postoperative radiographs. In the arthroscopic group, the extended-neck lateral α angle was reduced by a mean of 17.2° (28.3%, P < .05), AP α angle was reduced by a mean of 12.6° (16.8%), anterior head-neck offset improved 5.0 mm (111%, P < .05), and β angle increased by a mean of 23.1°. In the open dislocation group, the extended-neck lateral α angle was reduced by a mean of 21.2° (30.7%, P < .05), AP α angle was reduced by a mean of 20.1° (25.7%), anterior head-neck offset improved 6.56 mm (108%, P < .05), and β angle increased by a mean of 18.35°. Arthroscopic osteoplasty can restore head-neck offset and achieve similar depth, arc, and proximal-distal resection with comparable efficacy to open surgical dislocation for anterior and anterosuperior cam and focal rim impingement deformity. The open technique, however, may allow greater correction of posterosuperior loss of femoral offset and may be favorable for FAI patterns that demonstrate considerable proximal femoral deformity on AP radiographs.

  15. The role of a conserved proline residue in mediating conformational changes associated with voltage gating of Cx32 gap junctions.

    PubMed Central

    Ri, Y; Ballesteros, J A; Abrams, C K; Oh, S; Verselis, V K; Weinstein, H; Bargiello, T A

    1999-01-01

    We have explored the role of a proline residue located at position 87 in the second transmembrane segment (TM2) of gap junctions in the mechanism of voltage-dependent gating of connexin32 (Cx32). Substitution of this proline (denoted Cx32P87) with residues G, A, or V affects channel function in a progressive manner consistent with the expectation that a proline kink (PK) motif exists in the second transmembrane segment (TM2) of this connexin. Mutations of the preceding threonine residue T86 to S, A, C, V, N, or L shift the conductance-voltage relation of wild-type Cx32, such that the mutated channels close at smaller transjunctional voltages. The observed shift in voltage dependence is consistent with a reduction in the open probability of the mutant hemichannels at a transjunctional voltage (Vj) of 0 mV. In both cases in which kinetics were examined, the time constants for reaching steady state were faster for T86N and T86A than for wild type at comparable voltages, suggesting that the T86 mutations cause the energetic destabilization of the open state relative to the other states of the channel protein. The structural underpinnings of the observed effects were explored with Monte Carlo simulations. The conformational space of TM2 helices was found to differ for the T86A, V, N, and L mutants, which produce a less bent helix ( approximately 20 degrees bend angle) compared to the wild type, which has a approximately 37 degrees bend angle. The greater bend angle of the wild-type helix reflects the propensity of the T86 residue to hydrogen bond with the backbone carbonyl of amino acid residue I82. The relative differences in propensity for hydrogen bonding of the mutants relative to the wild-type threonine residue in the constructs we studied (T86A, V, N, L, S, and C) correlate with the shift in the conductance-voltage relation observed for T86 mutations. The data are consistent with a structural model in which the open conformation of the Cx32 channel corresponds to a more bent TM2 helix, and the closed conformation corresponds to a less bent helix. We propose that the modulation of the hydrogen-bonding potential of the T86 residue alters the bend angle of the PK motif and mediates conformational changes between open and closed channel states. PMID:10354417

  16. Correlations between Preoperative Angle Parameters and Postoperative Unpredicted Refractive Errors after Cataract Surgery in Open Angle Glaucoma (AOD 500).

    PubMed

    Lee, Wonseok; Bae, Hyoung Won; Lee, Si Hyung; Kim, Chan Yun; Seong, Gong Je

    2017-03-01

    To assess the accuracy of intraocular lens (IOL) power prediction for cataract surgery with open angle glaucoma (OAG) and to identify preoperative angle parameters correlated with postoperative unpredicted refractive errors. This study comprised 45 eyes from 45 OAG subjects and 63 eyes from 63 non-glaucomatous cataract subjects (controls). We investigated differences in preoperative predicted refractive errors and postoperative refractive errors for each group. Preoperative predicted refractive errors were obtained by biometry (IOL-master) and compared to postoperative refractive errors measured by auto-refractometer 2 months postoperatively. Anterior angle parameters were determined using swept source optical coherence tomography. We investigated correlations between preoperative angle parameters [angle open distance (AOD); trabecular iris surface area (TISA); angle recess area (ARA); trabecular iris angle (TIA)] and postoperative unpredicted refractive errors. In patients with OAG, significant differences were noted between preoperative predicted and postoperative real refractive errors, with more myopia than predicted. No significant differences were recorded in controls. Angle parameters (AOD, ARA, TISA, and TIA) at the superior and inferior quadrant were significantly correlated with differences between predicted and postoperative refractive errors in OAG patients (-0.321 to -0.408, p<0.05). Superior quadrant AOD 500 was significantly correlated with postoperative refractive differences in multivariate linear regression analysis (β=-2.925, R²=0.404). Clinically unpredicted refractive errors after cataract surgery were more common in OAG than in controls. Certain preoperative angle parameters, especially AOD 500 at the superior quadrant, were significantly correlated with these unpredicted errors.

  17. Correlations between Preoperative Angle Parameters and Postoperative Unpredicted Refractive Errors after Cataract Surgery in Open Angle Glaucoma (AOD 500)

    PubMed Central

    Lee, Wonseok; Bae, Hyoung Won; Lee, Si Hyung; Kim, Chan Yun

    2017-01-01

    Purpose To assess the accuracy of intraocular lens (IOL) power prediction for cataract surgery with open angle glaucoma (OAG) and to identify preoperative angle parameters correlated with postoperative unpredicted refractive errors. Materials and Methods This study comprised 45 eyes from 45 OAG subjects and 63 eyes from 63 non-glaucomatous cataract subjects (controls). We investigated differences in preoperative predicted refractive errors and postoperative refractive errors for each group. Preoperative predicted refractive errors were obtained by biometry (IOL-master) and compared to postoperative refractive errors measured by auto-refractometer 2 months postoperatively. Anterior angle parameters were determined using swept source optical coherence tomography. We investigated correlations between preoperative angle parameters [angle open distance (AOD); trabecular iris surface area (TISA); angle recess area (ARA); trabecular iris angle (TIA)] and postoperative unpredicted refractive errors. Results In patients with OAG, significant differences were noted between preoperative predicted and postoperative real refractive errors, with more myopia than predicted. No significant differences were recorded in controls. Angle parameters (AOD, ARA, TISA, and TIA) at the superior and inferior quadrant were significantly correlated with differences between predicted and postoperative refractive errors in OAG patients (-0.321 to -0.408, p<0.05). Superior quadrant AOD 500 was significantly correlated with postoperative refractive differences in multivariate linear regression analysis (β=-2.925, R2=0.404). Conclusion Clinically unpredicted refractive errors after cataract surgery were more common in OAG than in controls. Certain preoperative angle parameters, especially AOD 500 at the superior quadrant, were significantly correlated with these unpredicted errors. PMID:28120576

  18. [Studying the association between genetic polymorphism of growth factors and the development of primary open-angle glaucoma].

    PubMed

    Kirilenko, M Yu; Tikunova, E V; Sirotina, S S; Polonikov, A V; Bushueva, O Yu; Churnosov, M I

    Primary open-angle glaucoma (POAG) is a multifactorial disease, etiopathogenesis of which largely depends on growth factors. Possessing a variety of medical and biological effects, these cytokines may influence the development and progression of POAG. to reveal the role of genetic polymorphisms of growth factors in predisposition to developing POAG that is refractory to local hypotensive therapy. The object of the study were 162 patients with stage II-III POAG, in whom local hypotensive therapy was inefficient, 90 patients with stage II-III POAG well controlled on local hypotensive therapy, and 191 controls. The material for the study was venous blood taken from the cubital vein of a proband. Isolation of genomic DNA was performed by phenol-chloroform extraction. Analysis of genetic polymorphisms of growth factors was performed through allelic discrimination. For that, synthesis of DNA was carried out via polymerase chain reaction (PCR). It is found that the T IGFR-1 genetic variant (OR=1.34) and a combination of the C VEGF-A and T IGFR-1 genetic variants (OR=1.90) are risk factors of developing POAG that is refractory to local hypotensive therapy. A statistical model for predicting such a risk has been proposed that includes: VEGF-A с.-958C>T genetic marker (rs 833,061), age, concomitant non-inflammatory ocular diseases, microvascular changes in the conjunctiva, the degree of pigmentation of the angle of the anterior chamber, and pseudoexfoliative syndrome. Recognition accuracy of the model is 90.42%. The T IGFR-1 genetic variant and a combination of the C VEGF-A and T IGFR-1 genetic variants increase the risk of developing POAG that is refractory to local hypotensive therapy.

  19. Longitudinal analysis of progression in glaucoma using spectral-domain optical coherence tomography.

    PubMed

    Wessel, Julia M; Horn, Folkert K; Tornow, Ralf P; Schmid, Matthias; Mardin, Christian Y; Kruse, Friedrich E; Juenemann, Anselm G; Laemmer, Robert

    2013-05-01

    To compare the longitudinal loss of RNFL thickness measurements by SD-OCT in healthy individuals and glaucoma patients with or without progression concerning optic disc morphology. A total of 62 eyes, comprising 38 glaucomatous eyes with open angle glaucoma and 24 healthy controls, were included in the study (Erlangen Glaucoma Registry, NTC00494923). All patients were investigated annually over a period of 3 years by Spectralis SD-OCT measuring peripapillary RNFL thickness. By masked comparative analysis of photographs, the eyes were classified into nonprogressive and progressive glaucoma cases. Longitudinal loss of RNFL thickness was compared with morphological changes of optic disc morphology. Mixed model analysis of annual OCT scans revealed an estimated annual decrease of the RNFL thickness by 2.12 μm in glaucoma eyes with progression, whereas glaucoma eyes without progression in optic disc morphology lost 1.18 μm per year in RNFL thickness (P = 0.002). The rate of change in healthy eyes was 0.60 μm and thereby also significantly lower than in glaucoma eyes with progression (P < 0.001). The intrasession variability of three successive measurements without head repositioning was 1.5 ± 0.7 μm. The loss of mean RNFL thickness exceeded the intrasession variability in 60% of nonprogressive eyes, and in 85% of progressive eyes after 3 years. LONGITUDINAL MEASUREMENTS OF RNFL THICKNESS USING SD-OCT SHOW A MORE PRONOUNCED REDUCTION OF RNFL THICKNESS IN PATIENTS WITH PROGRESSION COMPARED WITH PATIENTS WITHOUT PROGRESSION IN GLAUCOMATOUS OPTIC DISC CHANGES. (www.clinicaltrials.gov number, NTC00494923.).

  20. Central corneal thickness and progression of the visual field and optic disc in glaucoma

    PubMed Central

    Chauhan, B C; Hutchison, D M; LeBlanc, R P; Artes, P H; Nicolela, M T

    2005-01-01

    Aims: To determine whether central corneal thickness (CCT) is a significant predictor of visual field and optic disc progression in open angle glaucoma. Methods: Data were obtained from a prospective study of glaucoma patients tested with static automated perimetry and confocal scanning laser tomography every 6 months. Progression was determined using a trend based approach called evidence of change (EOC) analysis in which sectoral ordinal scores based on the significance of regression coefficients of visual field pattern deviation and neuroretinal rim area over time are summed. Visual field progression was also determined using the event based glaucoma change probability (GCP) analysis using both total and pattern deviation. Results: The sample contained 101 eyes of 54 patients (mean (SD) age 56.5 (9.8) years) with a mean follow up of 9.2 (0.7) years and 20.7 (2.3) sets of examinations every 6 months. Lower CCT was associated with worse baseline visual fields and lower mean IOP in the follow up. In the longitudinal analysis CCT was not correlated with the EOC scores for visual field or optic disc change. In the GCP analyses, there was a tendency for groups classified as progressing to have lower CCT compared to non-progressing groups. In a multivariate analyses accounting for IOP, the opposite was found, whereby higher CCT was associated with visual field progression. None of the independent factors were predictive of optic disc progression. Conclusions: In this cohort of patients with established glaucoma, CCT was not a useful index in the risk assessment of visual field and optic disc progression. PMID:16024855

  1. Exclusion of chromosome 1q21-q31 from linkage to three pedigrees affected by the pigment-dispersion syndrome

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Paglinauan, C.; Haines, J.L.; Del Bono, E.A.

    1995-05-01

    The pigment-dispersion syndrome is a form of open-angle glaucoma that usually affects individuals in the first 3 decades of life. In addition to the typical optic-nerve degeneration seen in all types of glaucoma, the pigment-dispersion syndrome is characterized by distinctive clinical features including the deposition of pigment granules from the iris epithelium on a variety of ocular structures including the trabecular meshwork. Frequently this disorder affects young myopic individuals. In the early stages of the disease, affected individuals may have clinical evidence of dispersed pigment without an associated elevation of intraocular pressure and optic-nerve degeneration. However, as the disease processmore » progresses, many affected individuals ({approximately}50%) will develop elevated intraocular pressure and degeneration of the optic nerve, causing a permanent loss of sight. The pigment-dispersion syndrome shares several clinical features with the form of autosomal dominant juvenile open-angle glaucoma that recently has been mapped to the 1q21-q31 region of chromosome 1. Our results indicate that the pigment-dispersion syndrome, a form of glaucoma that may also affect the juvenile population, is genetically unrelated to the autosomal dominant form of juvenile glaucoma caused by a defect in a gene located in the 1q21-q31 region of chromosome 1. 15 refs., 2 figs., 1 tab.« less

  2. Evidence-based practice guideline of Chinese herbal medicine for primary open-angle glaucoma (qingfeng -neizhang)

    PubMed Central

    Yang, Yingxin; Ma, Qiu-yan; Yang, Yue; He, Yu-peng; Ma, Chao-ting; Li, Qiang; Jin, Ming; Chen, Wei

    2018-01-01

    Abstract Background: Primary open angle glaucoma (POAG) is a chronic, progressive optic neuropathy. The aim was to develop an evidence-based clinical practice guideline of Chinese herbal medicine (CHM) for POAG with focus on Chinese medicine pattern differentiation and treatment as well as approved herbal proprietary medicine. Methods: The guideline development group involved in various pieces of expertise in contents and methods. Authors searched electronic databases include CNKI, VIP, Sino-Med, Wanfang data, PubMed, the Cochrane Library, EMBASE, as well as checked China State Food and Drug Administration (SFDA) from the inception of these databases to June 30, 2015. Systematic reviews and randomized controlled trials of Chinese herbal medicine treating adults with POAG were evaluated. Risk of bias tool in the Cochrane Handbook and evidence strength developed by the GRADE group were applied for the evaluation, and recommendations were based on the findings incorporating evidence strength. After several rounds of Expert consensus, the final guideline was endorsed by relevant professional committees. Results: CHM treatment principle and formulae based on pattern differentiation together with approved patent herbal medicines are the main treatments for POAG, and the diagnosis and treatment focusing on blood related patterns is the major domain. Conclusion: CHM therapy alone or combined with other conventional treatment reported in clinical studies together with Expert consensus were recommended for clinical practice. PMID:29595636

  3. Pediatric cataract, myopic astigmatism, familial exudative vitreoretinopathy and primary open-angle glaucoma co-segregating in a family

    PubMed Central

    Hewitt, A.W.; Ruddle, J.B.; Vote, B.; Buttery, R.G.; Toomes, C.; Metlapally, R.; Li, Y.J.; Tran-Viet, K.N.; Malecaze, F.; Calvas, P.; Rosenberg, T.; Guggenheim, J.A.; Young, T.L.

    2011-01-01

    Purpose To describe an Australian pedigree of European descent with a variable autosomal dominant phenotype of: pediatric cortical cataract (CC), asymmetric myopia with astigmatism, familial exudative vitreoretinopathy (FEVR), and primary open-angle glaucoma (POAG). Methods Probands with CC, FEVR, and POAG were enrolled in three independent genetic eye studies in Tasmania. Genealogy confirmed these individuals were closely related and subsequent examination revealed 11 other family members with some or all of the associated disorders. Results Twelve individuals had CC thought to be of childhood onset, with one child demonstrating progressive lenticular opacification. One individual had severe retinal detachment while five others had dragged retinal vessels. Seven individuals had POAG. Seven individuals had myopia in at least one eye ≤-3 Diopters. DNA testing excluded mutations in myocilin, trabecular meshwork inducible glucocorticoid response (MYOC) and tetraspanin 12 (TSPAN12). Haplotype analysis excluded frizzled family receptor 4 (FZD4) and low density lipoprotein receptor-related protein 5 (LRP5), but only partly excluded EVR3. Multipoint linkage analysis revealed multiple chromosomal single-nucleotide polymorphisms (SNPs) of interest, but no statistically significant focal localization. Conclusions This unusual clustering of ophthalmic diseases suggests a possible single genetic cause for an apparently new cataract syndrome. This family’s clinical ocular features may reflect the interplay between retinal disease with lenticular changes and axial length in the development of myopia and glaucoma. PMID:21850187

  4. Pediatric cataract, myopic astigmatism, familial exudative vitreoretinopathy and primary open-angle glaucoma co-segregating in a family.

    PubMed

    Mackey, D A; Hewitt, A W; Ruddle, J B; Vote, B; Buttery, R G; Toomes, C; Metlapally, R; Li, Y J; Tran-Viet, K N; Malecaze, F; Calvas, P; Rosenberg, T; Guggenheim, J A; Young, T L

    2011-01-01

    To describe an Australian pedigree of European descent with a variable autosomal dominant phenotype of: pediatric cortical cataract (CC), asymmetric myopia with astigmatism, familial exudative vitreoretinopathy (FEVR), and primary open-angle glaucoma (POAG). Probands with CC, FEVR, and POAG were enrolled in three independent genetic eye studies in Tasmania. Genealogy confirmed these individuals were closely related and subsequent examination revealed 11 other family members with some or all of the associated disorders. Twelve individuals had CC thought to be of childhood onset, with one child demonstrating progressive lenticular opacification. One individual had severe retinal detachment while five others had dragged retinal vessels. Seven individuals had POAG. Seven individuals had myopia in at least one eye ≤-3 Diopters. DNA testing excluded mutations in myocilin, trabecular meshwork inducible glucocorticoid response (MYOC) and tetraspanin 12 (TSPAN12). Haplotype analysis excluded frizzled family receptor 4 (FZD4) and low density lipoprotein receptor-related protein 5 (LRP5), but only partly excluded EVR3. Multipoint linkage analysis revealed multiple chromosomal single-nucleotide polymorphisms (SNPs) of interest, but no statistically significant focal localization. This unusual clustering of ophthalmic diseases suggests a possible single genetic cause for an apparently new cataract syndrome. This family's clinical ocular features may reflect the interplay between retinal disease with lenticular changes and axial length in the development of myopia and glaucoma.

  5. Are we ready for genetic testing for primary open-angle glaucoma?

    PubMed

    Khawaja, Anthony P; Viswanathan, Ananth C

    2018-05-01

    Following a dramatic reduction in the cost of genotyping technology in recent years, there have been significant advances in the understanding of the genetic basis of glaucoma. Glaucoma patients represent around a quarter of all outpatient activity in the UK hospital eye service and are a huge burden for the National Health Service. A potential benefit of genetic testing is personalised glaucoma management, allowing direction of our limited healthcare resources to the glaucoma patients who most need it. Our review aims to summarise recent discoveries in the field of glaucoma genetics and to discuss their potential clinical utility. While genome-wide association studies have now identified over ten genes associated with primary open-angle glaucoma (POAG), individually, variants in these genes are not predictive of POAG in populations. There are data suggesting some of these POAG variants are associated with conversion from ocular hypertension to POAG and visual field progression among POAG patients. However, these studies have not been replicated yet and such genetic testing is not currently justified in clinical care. In contrast, genetic testing for inherited early-onset disease in relatives of POAG patients with a known genetic mutation is of clear benefit; this can support either regular review to commence early treatment when the disease develops, or discharge from ophthalmology services of relatives who do not carry the mutation. Genetic testing for POAG at a population level is not currently justified.

  6. Ultra-high resolution profiles of macular intra-retinal layer thicknesses and associations with visual field defects in primary open angle glaucoma

    NASA Astrophysics Data System (ADS)

    Chen, Qi; Huang, Shenghai; Ma, Qingkai; Lin, Huiling; Pan, Mengmeng; Liu, Xinting; Lu, Fan; Shen, Meixiao

    2017-02-01

    The structural characteristics of the outer retinal layers in primary open angle glaucoma (POAG) are still controversial, and these changes, along with those in the inner retinal layers, could have clinical and/or pathophysiological significance. A custom-built ultra-high resolution optical coherence tomography (UHR-OCT) combined with an automated segmentation algorithm can image and measure the eight intra-retinal layers. The purpose of this study is to determine the thickness characteristics of the macular intra-retinal layers, especially the outer layers, in POAG patients. Thirty-four POAG patients (56 eyes) and 33 normal subjects (63 eyes) were enrolled. Thickness profiles of the eight intra-retinal layers along a 6-mm length centred on the fovea at the horizontal and vertical meridians were obtained and the regional thicknesses were compared between two groups. The associations between the thicknesses of each intra-retinal layer and the macular visual field (VF) sensitivity were then analysed. POAG affected not only the inner retinal layers but also the photoreceptor layers and retinal pigment epithelium of the outer retina. However, the VF loss was correlated mainly with the damage of the inner retinal layers. UHR-OCT with automated algorithm is a useful tool in detecting microstructural changes of macula with respect to the progression of glaucoma.

  7. Predictors of Intraocular Pressure After Phacoemulsification in Primary Open-Angle Glaucoma Eyes with Wide Versus Narrower Angles (An American Ophthalmological Society Thesis)

    PubMed Central

    Lin, Shan C.; Masis, Marisse; Porco, Travis C.; Pasquale, Louis R.

    2017-01-01

    Purpose To assess if narrower-angle status and anterior segment optical coherence tomography (AS-OCT) parameters can predict intraocular pressure (IOP) drop in primary open-angle glaucoma (POAG) patients after cataract surgery. Methods This was a prospective case series of consecutive cataract surgery patients with POAG and no peripheral anterior synechiae (PAS) using a standardized postoperative management protocol. Preoperatively, patients underwent gonioscopy and AS-OCT. The same glaucoma medication regimen was resumed by 1 month. Potential predictors of IOP reduction included narrower-angle status by gonioscopy and angle-opening distance (AOD500) as well as other AS-OCT parameters. Mixed-effects regression adjusted for use of both eyes and other potential confounders. Results We enrolled 66 eyes of 40 glaucoma patients. The IOP reduction at 1 year was 4.2±3 mm Hg (26%, P<.001) in the narrower-angle group vs 2.2±3 mm Hg (14%, P<.001) in the wide-angle group (P=.027 for difference), as classified by gonioscopy. By AOD500 classification, the narrower-angle group had 3.4±3 mm Hg (21%, P<.001) reduction vs 2.5±3 mm Hg (16%, P<.001) in the wide-angle group (P=.031 for difference). When the entire cohort was assessed, iris thickness, iris area, and lens vault were correlated with increasing IOP reduction at 1 year (P<.05 for all). Conclusions In POAG eyes, cataract surgery lowered IOP to a greater degree in the narrower-angle group than in the wide-angle group, and parameters relating to iris thickness and area, as well as lens vault, were correlated with IOP reduction. These findings can guide ophthalmologists in their selection of cataract surgery as a potential management option. PMID:29147104

  8. Predictors of Intraocular Pressure After Phacoemulsification in Primary Open-Angle Glaucoma Eyes with Wide Versus Narrower Angles (An American Ophthalmological Society Thesis).

    PubMed

    Lin, Shan C; Masis, Marisse; Porco, Travis C; Pasquale, Louis R

    2017-08-01

    To assess if narrower-angle status and anterior segment optical coherence tomography (AS-OCT) parameters can predict intraocular pressure (IOP) drop in primary open-angle glaucoma (POAG) patients after cataract surgery. This was a prospective case series of consecutive cataract surgery patients with POAG and no peripheral anterior synechiae (PAS) using a standardized postoperative management protocol. Preoperatively, patients underwent gonioscopy and AS-OCT. The same glaucoma medication regimen was resumed by 1 month. Potential predictors of IOP reduction included narrower-angle status by gonioscopy and angle-opening distance (AOD500) as well as other AS-OCT parameters. Mixed-effects regression adjusted for use of both eyes and other potential confounders. We enrolled 66 eyes of 40 glaucoma patients. The IOP reduction at 1 year was 4.2±3 mm Hg (26%, P <.001) in the narrower-angle group vs 2.2±3 mm Hg (14%, P <.001) in the wide-angle group ( P =.027 for difference), as classified by gonioscopy. By AOD500 classification, the narrower-angle group had 3.4±3 mm Hg (21%, P <.001) reduction vs 2.5±3 mm Hg (16%, P <.001) in the wide-angle group ( P =.031 for difference). When the entire cohort was assessed, iris thickness, iris area, and lens vault were correlated with increasing IOP reduction at 1 year ( P <.05 for all). In POAG eyes, cataract surgery lowered IOP to a greater degree in the narrower-angle group than in the wide-angle group, and parameters relating to iris thickness and area, as well as lens vault, were correlated with IOP reduction. These findings can guide ophthalmologists in their selection of cataract surgery as a potential management option.

  9. Some Characteristics of Fuel Sprays from Open Nozzles

    NASA Technical Reports Server (NTRS)

    Rothrock, A M; Lee, D W

    1930-01-01

    The penetration and cone-angle of fuel sprays from open nozzles were recorded with the NACA Spray Photography Equipment. The results show that for injection systems in which the rate of pressure rise at the discharge orifice is high, open nozzles give spray-tip velocities and penetrations which compare favorably with those of closed nozzles. The spray cone-angle was the same for all tests, although open nozzles having different orifice diameters were used, and one nozzle was used both as an open and as a closed nozzle. In designing a fuel system using open nozzles, particular care must be taken to avoid air pockets. The check valve should be placed close to the discharge orifice.

  10. Baseline Fourier-Domain Optical Coherence Tomography Structural Risk Factors for Visual Field Progression in the Advanced Imaging for Glaucoma Study.

    PubMed

    Zhang, Xinbo; Dastiridou, Anna; Francis, Brian A; Tan, Ou; Varma, Rohit; Greenfield, David S; Schuman, Joel S; Sehi, Mitra; Chopra, Vikas; Huang, David

    2016-12-01

    To identify baseline structural parameters that predict the progression of visual field (VF) loss in patients with open-angle glaucoma. Multicenter cohort study. Participants from the Advanced Imaging for Glaucoma (AIG) study were enrolled and followed up. VF progression is defined as either a confirmed progression event on Humphrey Progression Analysis or a significant (P < .05) negative slope for VF index (VFI). Fourier-domain optical coherence tomography (FDOCT) was used to measure optic disc, peripapillary retinal nerve fiber layer (NFL), and macular ganglion cell complex (GCC) thickness parameters. A total of 277 eyes of 188 participants were followed up for 3.7 ± 2.1 years. VF progression was observed in 83 eyes (30%). Several baseline NFL and GCC parameters, but not disc parameters, were found to be significant predictors of progression on univariate Cox regression analysis. The most accurate single predictors were the GCC focal loss volume (FLV), followed closely by NFL-FLV. An abnormal GCC-FLV at baseline increased risk of progression by a hazard ratio of 3.1. Multivariate Cox analysis showed that combining age and central corneal thickness with GCC-FLV in a composite index called "Glaucoma Composite Progression Index" (GCPI) further improved the accuracy of progression prediction. GCC-FLV and GCPI were both found to be significantly correlated with the annual rate of change in VFI. Focal GCC and NFL loss as measured by FDOCT are the strongest predictors for VF progression among the measurements considered. Older age and thinner central corneal thickness can enhance the predictive power using the composite risk model. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Mild angle early onset idiopathic scoliosis children avoid progression under FITS method (Functional Individual Therapy of Scoliosis).

    PubMed

    Białek, Marianna

    2015-05-01

    Physiotherapy for stabilization of idiopathic scoliosis angle in growing children remains controversial. Notably, little data on effectiveness of physiotherapy in children with Early Onset Idiopathic Scoliosis (EOIS) has been published.The aim of this study was to check results of FITS physiotherapy in a group of children with EOIS.The charts of the patients archived in a prospectively collected database were retrospectively reviewed. The inclusion criteria were:diagnosis of EOIS based on spine radiography, age below 10 years, both girls and boys, Cobb angle between 118 and 308, Risser zero, FITS therapy, no other treatment (bracing), and a follow-up at least 2 years from the initiation of the treatment. The criterion for curve progression were as follows: the Cobb angle increase of 68 or more, for curve stabilization; the Cobb angle was 58 comparing to the initial radiograph,for curve correction; and the Cobb angle decrease of 68 or more at the final follow-up radiograph.There were 41 children with EOIS, 36 girls and 5 boys, mean age 7.71.3 years (range 4 to 9 years) who started FITS therapy. The curve pattern was single thoracic (5 children), single thoracolumbar (22 children) or double thoracic/thoracolumbar (14 children), totally 55 structural curvatures. The minimum follow-up was 2 years after initiation of the FITS treatment, maximum was 16 years, mean 4.8 years). At follow-up the mean age was 12.53.4 years. Out of 41 children, 10 passed pubertal growth spurt at the final follow-up and 31 were still immature and continued FITS therapy. Out of 41 children, 27 improved, 13 were stable, and one progressed. Out of 55 structural curves, 32 improved, 22 were stable and one progressed. For the 55 structural curves, the Cobb angle significantly decreased from 18.085.48 at first assessment to 12.586.38 at last evaluation,p<0.0001, paired t-test. The angle of trunk rotation decreased significantly from 4.782.98 to 3.282.58 at last evaluation, p<0.0001,paired t-test.FITS physiotherapy was effective in preventing curve progression in children with EOIS. Final postpubertal follow-up data is needed.

  12. MOJAVE - XIV. Shapes and opening angles of AGN jets

    NASA Astrophysics Data System (ADS)

    Pushkarev, A. B.; Kovalev, Y. Y.; Lister, M. L.; Savolainen, T.

    2017-07-01

    We present 15 GHz stacked VLBA images of 373 jets associated with active galactic nuclei (AGNs) having at least five observing epochs within a 20 yr time interval 1994-2015 from the Monitoring Of Jets in Active galactic nuclei with VLBA Experiments (MOJAVE) programme and/or its precursor, the 2-cm VLBA Survey. These data are supplemented by 1.4 GHz single-epoch VLBA observations of 135 MOJAVE AGNs to probe larger scale jet structures. The typical jet geometry is found to be close to conical on scales from hundreds to thousands of parsecs, while a number of galaxies show quasi-parabolic streamlines on smaller scales. A true jet geometry in a considerable fraction of AGNs appears only after stacking epochs over several years. The jets with significant radial accelerated motion undergo more active collimation. We have analysed total intensity jet profiles transverse to the local jet ridgeline and derived both apparent and intrinsic opening angles of the flows, with medians of 21.5° and 1.3°, respectively. The Fermi LAT-detected gamma-ray AGNs in our sample have, on average, wider apparent and narrower intrinsic opening angle, and smaller viewing angle than non-LAT-detected AGNs. We have established a highly significant correlation between the apparent opening angle and gamma-ray luminosity, driven by Doppler beaming and projection effects.

  13. Gravity field error analysis for pendulum formations by a semi-analytical approach

    NASA Astrophysics Data System (ADS)

    Li, Huishu; Reubelt, Tilo; Antoni, Markus; Sneeuw, Nico

    2017-03-01

    Many geoscience disciplines push for ever higher requirements on accuracy, homogeneity and time- and space-resolution of the Earth's gravity field. Apart from better instruments or new observables, alternative satellite formations could improve the signal and error structure compared to Grace. One possibility to increase the sensitivity and isotropy by adding cross-track information is a pair of satellites flying in a pendulum formation. This formation contains two satellites which have different ascending nodes and arguments of latitude, but have the same orbital height and inclination. In this study, the semi-analytical approach for efficient pre-mission error assessment is presented, and the transfer coefficients of range, range-rate and range-acceleration gravitational perturbations are derived analytically for the pendulum formation considering a set of opening angles. The new challenge is the time variations of the opening angle and the range, leading to temporally variable transfer coefficients. This is solved by Fourier expansion of the sine/cosine of the opening angle and the central angle. The transfer coefficients are further applied to assess the error patterns which are caused by different orbital parameters. The simulation results indicate that a significant improvement in accuracy and isotropy is obtained for small and medium initial opening angles of single polar pendulums, compared to Grace. The optimal initial opening angles are 45° and 15° for accuracy and isotropy, respectively. For a Bender configuration, which is constituted by a polar Grace and an inclined pendulum in this paper, the behaviour of results is dependent on the inclination (prograde vs. retrograde) and on the relative baseline orientation (left or right leading). The simulation for a sun-synchronous orbit shows better results for the left leading case.

  14. Flow field and performance characteristics of combustor diffusers: A basic study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hestermann, R.; Kim, S.; Ben Khaled, A.

    1995-10-01

    Results of a detailed study concerning the influence of geometric as well as fluid mechanic parameters o the performance of a plane model combustor diffuser in cold flow are presented. For a qualitative insight into the complex flow field inside the prediffuser, the sudden expansion region, and the flow field around the flame tube dome, results of a flow visualization study with the hydrogen bubble method as well as with the ink jet method are presented for different opening angles of the prediffuser and for different flame tube distances. Also, quantitative data from detailed measurements with LDV and conventional pressuremore » probes in a geometrically similar air-driven setup are presented. These data clearly demonstrate the effect of boundary layer thickness as well as the influence of different turbulence levels at the entry of the prediffuser on the performance characteristics of combustor diffusers. The possibility of getting an unseparated flow field inside the prediffuser even at large opening angles by appropriately matching the diffuser`s opening angle and the flame tube distance is demonstrated. Also, for flows with an increased turbulence level at the entrance--all other conditions held constant--an increased opening angle can be realized without experiencing flow separation. The comparison of the experimental data with predictions utilizing a finite-volume-code based on a body-fitted coordinate system for diffusers with an included total opening angle less than 18 deg demonstrates the capability of describing the flow field in combustor diffusers with reasonable accuracy.« less

  15. Effects of 2D and 3D Error Fields on the SAS Divertor Magnetic Topology

    NASA Astrophysics Data System (ADS)

    Trevisan, G. L.; Lao, L. L.; Strait, E. J.; Guo, H. Y.; Wu, W.; Evans, T. E.

    2016-10-01

    The successful design of plasma-facing components in fusion experiments is of paramount importance in both the operation of future reactors and in the modification of operating machines. Indeed, the Small Angle Slot (SAS) divertor concept, proposed for application on the DIII-D experiment, combines a small incident angle at the plasma strike point with a progressively opening slot, so as to better control heat flux and erosion in high-performance tokamak plasmas. Uncertainty quantification of the error fields expected around the striking point provides additional useful information in both the design and the modeling phases of the new divertor, in part due to the particular geometric requirement of the striking flux surfaces. The presented work involves both 2D and 3D magnetic error field analysis on the SAS strike point carried out using the EFIT code for 2D equilibrium reconstruction, V3POST for vacuum 3D computations and the OMFIT integrated modeling framework for data analysis. An uncertainty in the magnetic probes' signals is found to propagate non-linearly as an uncertainty in the striking point and angle, which can be quantified through statistical analysis to yield robust estimates. Work supported by contracts DE-FG02-95ER54309 and DE-FC02-04ER54698.

  16. Hong's grading for evaluating anterior chamber angle width.

    PubMed

    Kim, Seok Hwan; Kang, Ja Heon; Park, Ki Ho; Hong, Chul

    2012-11-01

    To compare Hong's grading method with anterior segment optical coherence tomography (AS-OCT), gonioscopy, and the dark-room prone-position test (DRPT) for evaluating anterior chamber width. The anterior chamber angle was graded using Hong's grading method, and Hong's angle width was calculated from the arctangent of Hong's grades. The correlation between Hong's angle width and AS-OCT parameters was analyzed. The area under the receiver operating characteristic curve (AUC) for Hong's grading method when discriminating between narrow and open angles as determined by gonioscopy was calculated. Correlation analysis was performed between Hong's angle width and intraocular pressure (IOP) changes determined by DRPT. A total of 60 subjects were enrolled. Of these subjects, 53.5 % had a narrow angle. Hong's angle width correlated significantly with the AS-OCT parameters (r = 0.562-0.719, P < 0.01). A Bland-Altman plot showed relatively good agreement between Hong's angle width and the angle width obtained by AS-OCT. The ability of Hong's grading method to discriminate between open and narrow angles was good (AUC = 0.868, 95 % CI 0.756-0.942). A significant linear correlation was found between Hong's angle width and IOP change determined by DRPT (r = -0.761, P < 0.01). Hong's grading method is useful for detecting narrow angles. Hong's grading correlated well with AS-OCT parameters and DRPT.

  17. Mechanical strength assessment of a drilled hole in the contralateral cortex at the end of the open wedge for high tibial osteotomy.

    PubMed

    Diffo Kaze, Arnaud; Maas, Stefan; Hoffmann, Alexander; Pape, Dietrich

    2017-12-01

    This study aimed to investigate, by means of finite element analysis, the effect of a drill hole at the end of a horizontal osteotomy to reduce the risk of lateral cortex fracture while performing an opening wedge high tibial osteotomy (OWHTO). The question was whether drilling a hole relieves stress and increases the maximum correction angle without fracture of the lateral cortex depending on the ductility of the cortical bone. Two different types of osteotomy cuts were considered; one with a drill hole (diameter 5 mm) and the other without the hole. The drill holes were located about 20 mm distally to the tibial plateau and 6 mm medially to the lateral cortex, such that the minimal thickness of the contralateral cortical bone was 5 mm. Based on finite element calculations, two approaches were used to compare the two types of osteotomy cuts considered: (1) Assessing the static strength using local stresses following the idea of the FKM-guideline, subsequently referred to as the "FKM approach" and (2) limiting the total strain during the opening of the osteotomy wedge, subsequently referred to as "strain approach". A critical opening angle leading to crack initiation in the opposite lateral cortex was determined for each approach and was defined as comparative parameter. The relation to bone aging was investigated by considering the material parameters of cortical bones from young and old subjects. The maximum equivalent (von-Mises) stress was smaller for the cases with a drill hole at the end of the osteotomy cut. The critical angle was approximately 1.5 times higher for the specimens with a drill hole compared to those without. This corresponds to an average increase of 50%. The calculated critical angle for all approaches is below 5°. The critical angle depends on the used approach, on patient's age and assumed ductility of the cortical bone. Drilling a hole at the end of the osteotomy reduces the stresses in the lateral cortex and increases the critical opening angle prior to cracking of the opposite cortex in specimen with small correction angles. But the difference from having a drill hole or not is not so significant, especially for older patients. The ductility of the cortical bone is the decisive parameter for the critical opening angle.

  18. Projected impact of travoprost versus both timolol and latanoprost on visual field deficit progression and costs among black glaucoma subjects.

    PubMed Central

    Halpern, Michael T; Covert, David W; Robin, Alan L

    2002-01-01

    PURPOSE: We compared differences associated with use of travoprost and latanoprost on both progression of perimetric loss over time and associated costs among black patients. METHODS: Patients with primary open-angle glaucome or ocular hypertension were randomly assigned to one of four arms in a 12-month, double-masked study: travoprost (0.004% or 0.0015%), latanoprost (0.005%), or timolol (0.5%). Forty-nine patients received 0.004% travoprost, 43 received latanoprost, and 40 received timolol. We applied algorithms found in published studies that link intraocular pressure (IOP) control to visual field progression and calculated the likelihood of visual field deterioration based on IOP data. This was used to estimate differences in medical care costs. RESULTS: The average IOP was lower for patients receiving travoprost than for patients receiving latanoprost or timolol (17.3 versus 18.7 versus 20.5 mm Hg respectively, P < .05). Travoprost-treated patients had a smaller predicted change in visual field defect score (VFDS) than latanoprost-treated patients and timolol-treated patients, and significantly fewer were expected to demonstrate visual field progression. Medical care costs would be higher for latanoprost-treated and timolol-treated patients. CONCLUSIONS: Recent studies have provided algorithms linking IOP control to changes in visual fields. We found that treatment with travoprost was associated with less visual field progression and potential cost savings. PMID:12545683

  19. Big Data and Deep data in scanning and electron microscopies: functionality from multidimensional data sets

    DOE PAGES

    Belianinov, Alex; Vasudevan, Rama K; Strelcov, Evgheni; ...

    2015-05-13

    The development of electron, and scanning probe microscopies in the second half of the twentieth century have produced spectacular images of internal structure and composition of matter with, at nanometer, molecular, and atomic resolution. Largely, this progress was enabled by computer-assisted methods of microscope operation, data acquisition and analysis. The progress in imaging technologies in the beginning of the twenty first century has opened the proverbial floodgates of high-veracity information on structure and functionality. High resolution imaging now allows information on atomic positions with picometer precision, allowing for quantitative measurements of individual bond length and angles. Functional imaging often leadsmore » to multidimensional data sets containing partial or full information on properties of interest, acquired as a function of multiple parameters (time, temperature, or other external stimuli). Here, we review several recent applications of the big and deep data analysis methods to visualize, compress, and translate this data into physically and chemically relevant information from imaging data.« less

  20. Big Data and Deep data in scanning and electron microscopies: functionality from multidimensional data sets

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Belianinov, Alex; Vasudevan, Rama K; Strelcov, Evgheni

    The development of electron, and scanning probe microscopies in the second half of the twentieth century have produced spectacular images of internal structure and composition of matter with, at nanometer, molecular, and atomic resolution. Largely, this progress was enabled by computer-assisted methods of microscope operation, data acquisition and analysis. The progress in imaging technologies in the beginning of the twenty first century has opened the proverbial floodgates of high-veracity information on structure and functionality. High resolution imaging now allows information on atomic positions with picometer precision, allowing for quantitative measurements of individual bond length and angles. Functional imaging often leadsmore » to multidimensional data sets containing partial or full information on properties of interest, acquired as a function of multiple parameters (time, temperature, or other external stimuli). Here, we review several recent applications of the big and deep data analysis methods to visualize, compress, and translate this data into physically and chemically relevant information from imaging data.« less

  1. A comparison of the sensitivity of EQ-5D, SF-6D and TTO utility values to changes in vision and perceived visual function in patients with primary open-angle glaucoma

    PubMed Central

    2012-01-01

    Background Economic viability of treatments for primary open-angle glaucoma (POAG) should be assessed objectively to prioritise health care interventions. This study aims to identify the methods for eliciting utility values (UVs) most sensitive to differences in visual field and visual functioning in patients with POAG. As a secondary objective, the dimensions of generic health-related and vision-related quality of life most affected by progressive vision loss will be identified. Methods A total of 132 POAG patients were recruited. Three sets of utility values (EuroQoL EQ-5D, Short Form SF-6D, Time Trade Off) and a measure of perceived visual functioning from the National Eye Institute Visual Function Questionnaire (VFQ-25) were elicited during face-to-face interviews. The sensitivity of UVs to differences in the binocular visual field, visual acuity and visual functioning measures was analysed using non-parametric statistical methods. Results Median utilities were similar across Integrated Visual Field score quartiles for EQ-5D (P = 0.08) whereas SF-6D and Time-Trade-Off UVs significantly decreased (p = 0.01 and p = 0.001, respectively). The VFQ-25 score varied across Integrated Visual Field and binocular visual acuity groups and was associated with all three UVs (P ≤ 0.001); most of its vision-specific sub-scales were associated with the vision markers. The most affected dimension was driving. A relationship with vision markers was found for the physical component of SF-36 and not for any dimension of EQ-5D. Conclusions The Time-Trade-Off was more sensitive than EQ-5D and SF-6D to changes in vision and visual functioning associated with glaucoma progression but could not measure quality of life changes in the mildest disease stages. PMID:22909264

  2. 46 CFR 172.150 - Survival conditions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... waterline, in the final condition of sinkage, heel, and trim, must be below the lower edge of openings such.... (5) Side scuttles of the non-opening type. (b) Heel angle. (1) Except as described in paragraph (b)(2) of this section, the maximum angle of heel must not exceed 15 degrees (17 degrees if no part of the...

  3. 46 CFR 172.150 - Survival conditions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... waterline, in the final condition of sinkage, heel, and trim, must be below the lower edge of openings such.... (5) Side scuttles of the non-opening type. (b) Heel angle. (1) Except as described in paragraph (b)(2) of this section, the maximum angle of heel must not exceed 15 degrees (17 degrees if no part of the...

  4. Ocular Biometrics of Myopic Eyes With Narrow Angles.

    PubMed

    Chong, Gabriel T; Wen, Joanne C; Su, Daniel Hsien-Wen; Stinnett, Sandra; Asrani, Sanjay

    2016-02-01

    The purpose of this study was to compare the ocular biometrics between myopic patients with and without narrow angles. Patients with a stable myopic refraction (myopia worse than -1.00 D spherical equivalent) were prospectively recruited. Angle status was assessed using gonioscopy and biometric measurements were performed using an anterior segment optical coherence tomography and an IOLMaster. A total of 29 patients (58 eyes) were enrolled with 13 patients (26 eyes) classified as having narrow angles and 16 patients (32 eyes) classified as having open angles. Baseline demographics of age, sex, and ethnicity did not differ significantly between the 2 groups. The patients with narrow angles were on average older than those with open angles but the difference did not reach statistical significance (P=0.12). The central anterior chamber depth was significantly less in the eyes with narrow angles (P=0.05). However, the average lens thickness, although greater in the eyes with narrow angles, did not reach statistical significance (P=0.10). Refractive error, axial lengths, and iris thicknesses did not differ significantly between the 2 groups (P=0.32, 0.47, 0.15). Narrow angles can occur in myopic eyes. Routine gonioscopy is therefore recommended for all patients regardless of refractive error.

  5. Comparison of Standard Automated Perimetry, Short-Wavelength Automated Perimetry, and Frequency-Doubling Technology Perimetry to Monitor Glaucoma Progression

    PubMed Central

    Hu, Rongrong; Wang, Chenkun; Gu, Yangshun; Racette, Lyne

    2016-01-01

    Abstract Detection of progression is paramount to the clinical management of glaucoma. Our goal is to compare the performance of standard automated perimetry (SAP), short-wavelength automated perimetry (SWAP), and frequency-doubling technology (FDT) perimetry in monitoring glaucoma progression. Longitudinal data of paired SAP, SWAP, and FDT from 113 eyes with primary open-angle glaucoma enrolled in the Diagnostic Innovations in Glaucoma Study or the African Descent and Glaucoma Evaluation Study were included. Data from all tests were expressed in comparable units by converting the sensitivity from decibels to unitless contrast sensitivity and by expressing sensitivity values in percent of mean normal based on an independent dataset of 207 healthy eyes with aging deterioration taken into consideration. Pointwise linear regression analysis was performed and 3 criteria (conservative, moderate, and liberal) were used to define progression and improvement. Global mean sensitivity (MS) was fitted with linear mixed models. No statistically significant difference in the proportion of progressing and improving eyes was observed across tests using the conservative criterion. Fewer eyes showed improvement on SAP compared to SWAP and FDT using the moderate criterion; and FDT detected less progressing eyes than SAP and SWAP using the liberal criterion. The agreement between these test types was poor. The linear mixed model showed a progressing trend of global MS overtime for SAP and SWAP, but not for FDT. The baseline estimate of SWAP MS was significantly lower than SAP MS by 21.59% of mean normal. FDT showed comparable estimation of baseline MS with SAP. SWAP and FDT do not appear to have significant benefits over SAP in monitoring glaucoma progression. SAP, SWAP, and FDT may, however, detect progression in different glaucoma eyes. PMID:26886602

  6. Multifocal VEP and OCT findings in patients with primary open angle glaucoma: A cross-sectional study

    PubMed Central

    2012-01-01

    Bakground To evaluate objectively the anatomical and functional changes of optic nerve in eyes with primary open angle glaucoma (POAG) by the joint use of optical coherence tomography (OCT) and multifocal visual evoked potentials (mfVEP). Methods 29 eyes with open angle glaucoma and visual field defects, as well as 20 eyes of 10 age-matched control normal subjects were tested. All participants underwent a complete ophthalmological examination. Moreover, Humphrey visual field test, OCT examination and recording of mfVEP were performed. Amplitude and implicit time of mfVEP, as well as RNFL thickness were measured. Differences in density components of mfVEP and in RNFL thickness among POAG eyes and control eyes were examined using Student’s t-test. Results In glaucomatous eyes the mean Retinal Response Density (RRD) was lower than normal in ring 1, 2 and 3 of mfVEP (p < 0.0001). Specifically the mean amplitude of mfVEP in POAG eyes was estimated at 34.2 ± 17.6 nV/deg2, 6.9 ± 4.8 nV/deg2 and 2.6 ± 1.6 nV/deg2 in rings 1, 2 and 3 respectively. In contrast the mean implicit time was similar to control eyes. In addition, the mean RNFL thickness in POAG eyes was estimated at 76.8 ± 26.6 μm in the superior area, 52.1 ± 16.3 μm in the temporal area, 75.9 ± 32.5 μm in the inferior area and 58.6 ± 19.4 μm in the nasal area. There was a statistically significant difference in RNFL thickness in all peripapillary areas (p < 0.0001) between POAG eyes and controls, with superior and inferior area to present the highest decrease. Conclusions Our study shows that, although Standard Automatic Perimetry is the gold standard to evaluate glaucomatous neuropathy, the joint use of mfVEP and OCT could be useful in better monitoring glaucoma progression. PMID:22856337

  7. Energy Landscapes for the Self-Assembly of Supramolecular Polyhedra

    NASA Astrophysics Data System (ADS)

    Russell, Emily R.; Menon, Govind

    2016-06-01

    We develop a mathematical model for the energy landscape of polyhedral supramolecular cages recently synthesized by self-assembly (Sun et al. in Science 328:1144-1147, 2010). Our model includes two essential features of the experiment: (1) geometry of the organic ligands and metallic ions; and (2) combinatorics. The molecular geometry is used to introduce an energy that favors square-planar vertices (modeling {Pd}^{2+} ions) and bent edges with one of two preferred opening angles (modeling boomerang-shaped ligands of two types). The combinatorics of the model involve two-colorings of edges of polyhedra with four-valent vertices. The set of such two-colorings, quotiented by the octahedral symmetry group, has a natural graph structure and is called the combinatorial configuration space. The energy landscape of our model is the energy of each state in the combinatorial configuration space. The challenge in the computation of the energy landscape is a combinatorial explosion in the number of two-colorings of edges. We describe sampling methods based on the symmetries of the configurations and connectivity of the configuration graph. When the two preferred opening angles encompass the geometrically ideal angle, the energy landscape exhibits a very low-energy minimum for the most symmetric configuration at equal mixing of the two angles, even when the average opening angle does not match the ideal angle.

  8. Satellite-Tracking Millimeter-Wave Reflector Antenna System For Mobile Satellite-Tracking

    NASA Technical Reports Server (NTRS)

    Densmore, Arthur C. (Inventor); Jamnejad, Vahraz (Inventor); Woo, Kenneth E. (Inventor)

    2001-01-01

    A miniature dual-band two-way mobile satellite-tracking antenna system mounted on a movable vehicle includes a miniature parabolic reflector dish having an elliptical aperture with major and minor elliptical axes aligned horizontally and vertically, respectively, to maximize azimuthal directionality and minimize elevational directionality to an extent corresponding to expected pitch excursions of the movable ground vehicle. A feed-horn has a back end and an open front end facing the reflector dish and has vertical side walls opening out from the back end to the front end at a lesser horn angle and horizontal top and bottom walls opening out from the back end to the front end at a greater horn angle. An RF circuit couples two different signal bands between the feed-horn and the user. An antenna attitude controller maintains an antenna azimuth direction relative to the satellite by rotating it in azimuth in response to sensed yaw motions of the movable ground vehicle so as to compensate for the yaw motions to within a pointing error angle. The controller sinusoidally dithers the antenna through a small azimuth dither angle greater than the pointing error angle while sensing a signal from the satellite received at the reflector dish, and deduces the pointing angle error from dither-induced fluctuations in the received signal.

  9. A satellite-tracking millimeter-wave reflector antenna system for mobile satellite-tracking

    NASA Technical Reports Server (NTRS)

    Densmore, Arthur C. (Inventor); Jamnejad, Vahraz (Inventor); Woo, Kenneth E. (Inventor)

    1995-01-01

    A miniature dual-band two-way mobile satellite tracking antenna system mounted on a movable ground vehicle includes a miniature parabolic reflector dish having an elliptical aperture with major and minor elliptical axes aligned horizontally and vertically, respectively, to maximize azimuthal directionality and minimize elevational directionality to an extent corresponding to expected pitch excursions of the movable ground vehicle. A feed-horn has a back end and an open front end facing the reflector dish and has vertical side walls opening out from the back end to the front end at a lesser horn angle and horizontal top and bottom walls opening out from the back end to the front end at a greater horn angle. An RF circuit couples two different signal bands between the feed-horn and the user. An antenna attitude controller maintains an antenna azimuth direction relative to the satellite by rotating it in azimuth in response to sensed yaw motions of the movable ground vehicle so as to compensate for the yaw motions to within a pointing error angle. The controller sinusoidally dithers the antenna through a small azimuth dither angle greater than the pointing error angle while sensing a signal from the satellite received at the reflector dish, and deduces the pointing angle error from dither-induced fluctuations in the received signal.

  10. Characteristics of Upper Quadrant Posture of Young Women with Temporomandibular Disorders

    PubMed Central

    Uritani, Daisuke; Kawakami, Tetsuji; Inoue, Tomohiro; Kirita, Tadaaki

    2014-01-01

    [Purpose] This study aimed to investigate the characteristics of upper quadrant posture of young women with temporomandibular disorders. [Subjects] The participants were 19 female patients with temporomandibular disorders (patient group: mean age, 30.1 years) and 14 controls (control group: mean age, 24.6 years). [Methods] Outcome measures were the neck inclination angle (formed by a line connecting C7 and the ear tragus with a horizontal line), the angle of the shoulder (formed by a line connecting C7 and the acromial angle with a horizontal line), the cranial rotation angle (formed by a line connecting the ear tragus and the corner of the eye with a horizontal line), and the neck-length/shoulder-width ratio [the ratio of the neck length (from C7 to the tragus) to the width of the shoulder between the acromial angle]. The maximum range of mouth opening was measured using a scale. [Results] The neck inclination angle and maximum range of mouth opening were significantly smaller in the patient group than in the control group. No significant differences were observed in the other outcome measures between the two groups. [Conclusion] Temporomandibular disorders with limited mouth opening in young females are associated with the head position relative to the trunk. PMID:25276038

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goldstein, Adam; Connaughton, Valerie; Briggs, Michael S.

    We present a method to estimate the jet opening angles of long duration gamma-ray bursts (GRBs) using the prompt gamma-ray energetics and an inversion of the Ghirlanda relation, which is a correlation between the time-integrated peak energy of the GRB prompt spectrum and the collimation-corrected energy in gamma-rays. The derived jet opening angles using this method and detailed assumptions match well with the corresponding inferred jet opening angles obtained when a break in the afterglow is observed. Furthermore, using a model of the predicted long GRB redshift probability distribution observable by the Fermi Gamma-ray Burst Monitor (GBM), we estimate themore » probability distributions for the jet opening angle and rest-frame energetics for a large sample of GBM GRBs for which the redshifts have not been observed. Previous studies have only used a handful of GRBs to estimate these properties due to the paucity of observed afterglow jet breaks, spectroscopic redshifts, and comprehensive prompt gamma-ray observations, and we potentially expand the number of GRBs that can be used in this analysis by more than an order of magnitude. In this analysis, we also present an inferred distribution of jet breaks which indicates that a large fraction of jet breaks are not observable with current instrumentation and observing strategies. We present simple parameterizations for the jet angle, energetics, and jet break distributions so that they may be used in future studies.« less

  12. Progress towards extreme attitude testing with Magnetic Suspension and Balance Systems

    NASA Technical Reports Server (NTRS)

    Britcher, Colin P.; Parker, David H.

    1988-01-01

    Progress is reported in a research effort aimed towards demonstration of the feasibility of suspension and aerodynamic testing of models at high angles of attack in wind tunnel Magnetic Suspension and Balance Systems. Extensive modifications, described in this paper, have been made to the Southampton University suspension system in order to facilitate this work. They include revision of electromagnet configuration, installation of all-new position sensors and expansion of control system programs. An angle of attack range of 0 to 90 deg is expected for axisymmetric models. To date, suspension up to 80 deg angle of attack has been achieved.

  13. Cross Cell Sandwich Core

    NASA Technical Reports Server (NTRS)

    Ford, Donald B. (Inventor)

    2004-01-01

    A sandwich core comprises two faceplates separated by a plurality of cells. The cells are comprised of walls positioned at oblique angles relative to a perpendicular axis extending through the faceplates. The walls preferably form open cells and are constructed from open cells and are constructed from rows of ribbons. The walls may be obliquely angled relative to more than one plane extending through the perpendicular axis.

  14. Heterogeneous growth-induced prestrain in the heart

    PubMed Central

    Genet, M.; Rausch, M.; Lee, L.C.; Choy, S.; Zhao, X.; Kassab, G.S.; Kozerke, S.; Guccione, J.M.; Kuhl, E.

    2015-01-01

    Even when entirely unloaded, biological structures are not stress-free, as shown by Y.C. Fung’s seminal opening angle experiment on arteries and the left ventricle. As a result of this prestrain, subject-specific geometries extracted from medical imaging do not represent an unloaded reference configuration necessary for mechanical analysis, even if the structure is externally unloaded. Here we propose a new computational method to create physiological residual stress fields in subject-specific left ventricular geometries using the continuum theory of fictitious configurations combined with a fixed-point iteration. We also reproduced the opening angle experiment on four swine models, to characterize the range of normal opening angle values. The proposed method generates residual stress fields which can reliably reproduce the range of opening angles between 8.7±1.8 and 16.6 ± 13.7 as measured experimentally. We demonstrate that including the effects of prestrain reduces the left ventricular stiffness by up to 40%, thus facilitating the ventricular filling, which has a significant impact on cardiac function. This method can improve the fidelity of subject-specific models to improve our understanding of cardiac diseases and to optimize treatment options. PMID:25913241

  15. Refraction and scattering of sound by a shear layer

    NASA Technical Reports Server (NTRS)

    Schlinker, R. H.; Amiet, R. K.

    1980-01-01

    The angle and amplitude changes for acoustic waves refracted by a circular open jet shear layer were determined. The generalized refraction theory was assessed experimentally for on axis and off axis acoustic source locations as source frequency varied from 1 kHz to 10 kHz and free stream Mach number varied from 0.1 to 0.4. Angle and amplitude changes across the shear layer show good agreement with theory. Experiments confirm that the refraction theory is independent of shear layer thickness, acoustic source frequency, and source type. A generalized theory is, thus, available for correcting far field noise data acquired in open jet test facilities. The effect of discrete tone scattering by the open jet turbulent shear layer was also studied. Scattering effects were investigated over the same Mach number range as frequency varied from 5 kHz to 15 kHz. Attenuation of discrete tone amplitude and tone broadening were measured as a function of acoustic source position and radiation angle. Scattering was found to be stronger at angles close to the open jet axis than at 90 deg, and becomes stronger as the acoustic source position shifts downstream. A scattering analysis provided an estimate of the onset of discrete tone scattering.

  16. Retrobulbar hemodynamic parameters in men and women with open angle glaucoma.

    PubMed

    Marjanović, Ivan; Marjanović, Marija; Gvozdenović, Ranko; Risović, Dušica

    2014-12-01

    Several factors may have influence on systemic circulation. Additionally, peripheral circulation also demonstrates sex differences, in young women presenting significantly lower finger blood flow in comparison to men of the same age, a finding that disappears in women after menopause. The aim of this study was to compare the retrobulbar hemodynamic parameters measured by means of color Doppler imaging in women and men with open-angle glaucoma and elevated intraocular pressure. A total of 52 eyes from 52 open-angle glaucoma (OAG) patients, with elevated intraocular pressure (lOP), were included in this cross-sectional study. Peak-systolic velocity (PSV), end-diastolic velocity (EDV), and Pourcelot resistivity index (RI) were assessed in the ophtalmic artery (OA), central retinal artery (CRA), and posterior cilliary arteries (PCA). IOP was measured both with Goldmann Applanation tonometer (GAT) and with the dynamic contour tonometer (DCT), three times respectively. Ocular pulse amplitude (OPA) appeared during the DCT measurement. The retrobulbar hemodynamic parameters did not show any difference between men and post-menopausal women. The results of our study did not find any difference between sexes in patients with open-angle glaucoma and elevated intraocular pressure.

  17. Measurement of fetal head descent using the 'angle of progression' on transperineal ultrasound imaging is reliable regardless of fetal head station or ultrasound expertise.

    PubMed

    Dückelmann, A M; Bamberg, C; Michaelis, S A M; Lange, J; Nonnenmacher, A; Dudenhausen, J W; Kalache, K D

    2010-02-01

    To assess whether ultrasound experience or fetal head station affects the reliability of measurement of fetal head descent using the angle of progression on intrapartum ultrasound images obtained by a single experienced operator, and to determine reliability of measurements when images were acquired by different operators with variable ultrasound experience. One experienced obstetrician performed 44 transperineal ultrasound examinations of women at term and in prolonged second stage of labor with the fetus in the occipitoanterior position. Three midwives without ultrasound experience, three obstetricians with < 5 years' experience and three obstetricians with > 10 years' experience measured fetal head descent based on the angle of progression in the images obtained. The angle of progression was measured by two obstetricians in independent ultrasound examinations of 24 laboring women at term with the fetus in the cephalic position to allow assessment of the reliability of image acquisition. Intraclass correlation coefficients (ICCs) with 95% confidence interval (CI) were used to evaluate interobserver reliability and Bland-Altman analysis was used to assess interobserver agreement. In total, 444 measurements were performed and compared. Interobserver reliability with respect to offline image analysis was substantial (overall ICC, 0.72; 95% CI, 0.63-0.81). ICCs were 0.82 (95% CI, 0.70-0.89), 0.81 (95% CI, 0.71-0.88) and 0.61 (95% CI, 0.43-074) for observers with > 10 years', < 5 years' and no ultrasound experience, respectively. There were no significant differences between ICCs among observer groups according to ultrasound experience. Fetal head station did not affect reliability. Bland-Altman analysis indicated reasonable agreement between measurements obtained by two different operators with > 10 years' and < 5 years' ultrasound experience (bias, -1.09 degrees ; 95% limits of agreement, -8.76 to 6.58). The reliability of measurement of the angle of progression following separate image acquisition by two experienced operators was similar to the reliability of offline image analysis (ICC, 0.86; 95% CI, 0.70-0.93). Measurement of the angle of progression on transperineal ultrasound imaging is reliable regardless of fetal head station or the clinician's level of ultrasound experience.

  18. Accurate Analysis of Target Characteristic in Bistatic SAR Images: A Dihedral Corner Reflectors Case.

    PubMed

    Ao, Dongyang; Li, Yuanhao; Hu, Cheng; Tian, Weiming

    2017-12-22

    The dihedral corner reflectors are the basic geometric structure of many targets and are the main contributions of radar cross section (RCS) in the synthetic aperture radar (SAR) images. In stealth technologies, the elaborate design of the dihedral corners with different opening angles is a useful approach to reduce the high RCS generated by multiple reflections. As bistatic synthetic aperture sensors have flexible geometric configurations and are sensitive to the dihedral corners with different opening angles, they specially fit for the stealth target detections. In this paper, the scattering characteristic of dihedral corner reflectors is accurately analyzed in bistatic synthetic aperture images. The variation of RCS with the changing opening angle is formulated and the method to design a proper bistatic radar for maximizing the detection capability is provided. Both the results of the theoretical analysis and the experiments show the bistatic SAR could detect the dihedral corners, under a certain bistatic angle which is related to the geometry of target structures.

  19. Accurate Analysis of Target Characteristic in Bistatic SAR Images: A Dihedral Corner Reflectors Case

    PubMed Central

    Ao, Dongyang; Hu, Cheng; Tian, Weiming

    2017-01-01

    The dihedral corner reflectors are the basic geometric structure of many targets and are the main contributions of radar cross section (RCS) in the synthetic aperture radar (SAR) images. In stealth technologies, the elaborate design of the dihedral corners with different opening angles is a useful approach to reduce the high RCS generated by multiple reflections. As bistatic synthetic aperture sensors have flexible geometric configurations and are sensitive to the dihedral corners with different opening angles, they specially fit for the stealth target detections. In this paper, the scattering characteristic of dihedral corner reflectors is accurately analyzed in bistatic synthetic aperture images. The variation of RCS with the changing opening angle is formulated and the method to design a proper bistatic radar for maximizing the detection capability is provided. Both the results of the theoretical analysis and the experiments show the bistatic SAR could detect the dihedral corners, under a certain bistatic angle which is related to the geometry of target structures. PMID:29271917

  20. --No Title--

    Science.gov Websites

    : "\\f106"; /* open - switch to fa-angle-up */ } @media(min-width:768px) { /* top level open */ } } /* top level open hover */ .navbar-dark .navbar-nav > li.open > a:hover, .navbar-dark .navbar-nav :768px) { /* top level open hover desktop*/ .navbar-dark .navbar-nav > li.open > a:hover, .navbar

  1. Instantaneous progression reference frame for calculating pelvis rotations: Reliable and anatomically-meaningful results independent of the direction of movement.

    PubMed

    Kainz, Hans; Lloyd, David G; Walsh, Henry P J; Carty, Christopher P

    2016-05-01

    In motion analysis, pelvis angles are conventionally calculated as the rotations between the pelvis and laboratory reference frame. This approach assumes that the participant's motion is along the anterior-posterior laboratory reference frame axis. When this assumption is violated interpretation of pelvis angels become problematic. In this paper a new approach for calculating pelvis angles based on the rotations between the pelvis and an instantaneous progression reference frame was introduced. At every time-point, the tangent to the trajectory of the midpoint of the pelvis projected into the horizontal plane of the laboratory reference frame was used to define the anterior-posterior axis of the instantaneous progression reference frame. This new approach combined with the rotation-obliquity-tilt rotation sequence was compared to the conventional approach using the rotation-obliquity-tilt and tilt-obliquity-rotation sequences. Four different movement tasks performed by eight healthy adults were analysed. The instantaneous progression reference frame approach was the only approach that showed reliable and anatomically meaningful results for all analysed movement tasks (mean root-mean-square-differences below 5°, differences in pelvis angles at pre-defined gait events below 10°). Both rotation sequences combined with the conventional approach led to unreliable results as soon as the participant's motion was not along the anterior-posterior laboratory axis (mean root-mean-square-differences up to 30°, differences in pelvis angles at pre-defined gait events up to 45°). The instantaneous progression reference frame approach enables the gait analysis community to analysis pelvis angles for movements that do not follow the anterior-posterior axis of the laboratory reference frame. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Current concepts on primary open-angle glaucoma genetics: a contribution to disease pathophysiology and future treatment

    PubMed Central

    Gemenetzi, M; Yang, Y; Lotery, A J

    2012-01-01

    Glaucoma is a common, complex, heterogenous disease and it constitutes the major cause of irreversible blindness worldwide. Primary open-angle glaucoma (POAG) is the most common type of glaucoma in all populations. Most of the molecular mechanisms leading to POAG development are still unknown. Gene mutations in various populations have been identified by genetic studies and a genetic basis for glaucoma pathogenesis has been established. Linkage analysis and association studies are genetic approaches in the investigation of the genetic basis of POAG. Genome-wide association studies (GWAS) are more powerful compared with linkage analysis in discovering genes of small effect that might contribute to the development of the disease. POAG links to at least 20 genetic loci, but only 2 genes identified in these loci, myocilin and optineurin, are considered as well-established glaucoma-causing genes, whereas the role of other loci, genes, and variants implicated in the development of POAG remains controversial. Gene mutations associated with POAG result in retinal ganglion cell death, which is the common outcome of pathogenetic mechanisms in glaucoma. In future, if the sensitivity and specificity of genotyping increases, it may be possible to screen individuals routinely for disease susceptibility. This review is an update on the latest progress of genetic studies associated with POAG. It emphasizes the correlation of recent achievements in genetics with glaucoma pathophysiology, glaucoma treatment perspectives, and the possibility of future prevention of irreversible visual loss caused by the disease. PMID:22173078

  3. Aerodynamic Load Measurements and Opening Characteristics of Automatic Leading Edge Slats on a 45 deg Sweptback Wing at Transonic Speeds

    NASA Technical Reports Server (NTRS)

    Arabian, Donald D.; Runckel, Jack F.; Reid, Charles F, Jr.

    1961-01-01

    Measurements of the normal force and chord force were made on the slats of a sting-mounted wing-fuselage model through a Mach number range of 0.60 to 1.03 and at angles of attack from 0 to 20 deg at subsonic speeds and from 0 to 8 deg at Mach number 1.03. The 20-percent-chord tapered leading-edge slats extended from 25 to 95 percent of the semispan and consisted of five segments. The model wing had 45 deg sweep, an aspect ratio of 3.56, a taper ratio of 0.3, and NACA 64(06)AO07 airfoil sections. Slat forces and moments were determined for the slats in the almost-closed and open positions for spanwise extents of 35 to 95 percent and 46 to 95 percent of the semispan. The results of the investigation showed little change in the slat maximum force and moment coefficients with Mach number. The coefficients for the open and almost-closed slat positions had similar variations with angle of attack. The loads on the individual slat segments were found to increase toward the tip for moderate angles of attack and decrease toward the tip for high angles of attack. An analysis of the opening and closing characteristics of aerodynamically operated slats opening on a circular-arc path is included.

  4. A mechanical analysis of conduit arteries accounting for longitudinal residual strains.

    PubMed

    Wang, Ruoya; Gleason, Rudolph L

    2010-04-01

    Identification of an appropriate stress-free reference configuration is critically important in providing a reasonable prediction of the intramural stress distribution when performing biomechanical analyses on arteries. The stress-free state is commonly approximated as a radially cut ring that typically opens into a nearly circular sector, relieving much of the circumferential residual strains that exist in the traction-free configuration. An opening angle is often used to characterize this sector. In this study, we first present experimental results showing significant residual deformations in the longitudinal direction of two commonly studied arteries in the pig: the common carotid artery and the left anterior descending coronary artery. We concluded that a radially cut ring cannot completely describe the stress-free state of the arteries. Instead, we propose the use of a longitudinal opening angle, in conjunction with the traditional circumferential opening angle, to experimentally quantify the stress-free state of an artery. Secondly, we propose a new kinematic model to account for the addition of longitudinal residual strains through employing the longitudinal opening angle and performed a stress analysis. We found that with the inclusion of longitudinal residual strains in the stress analysis, the predicted circumferential stress gradient was decreased by 3-fold and the predicted longitudinal stress gradient was increased by 5.7-fold. Thus, inclusion of longitudinal residual strains has a significant effect on the predicted stress distribution in arteries.

  5. The effect of internal fixation lamp on anterior chamber angle width measured by anterior segment optical coherence tomography.

    PubMed

    Nakamine, Sakari; Sakai, Hiroshi; Arakaki, Yoshikuni; Yonahara, Michiko; Kaiya, Tadayoshi

    2018-01-01

    To study the effect of the internal fixation lamp on anterior chamber width measured by anterior segment optical coherence tomography. In a prospective cross sectional observational study, consecutive 22 right eyes of 22 patients (4 men and 18 women) with suspected primary angle closure underwent swept source domain anterior segment optical coherence tomography (AS-OCT), (CASIA SS-1000, Tomey, Nagoya, Japan). Anterior chamber parameters of angle opening distance (AOD), trabecular-iris angle (TIA), angle recess area (ARA) at 500 or 750 µm from scleral spur and pupil diameter were measured by AS-OCT in a three-dimensional mode in 4 quadrants (superior, inferior, temporal and nasal) in dark room setting both with and without internal fixation lamp. Anterior segment parameters of AOD 500 in superior, inferior and temporal quadrants, AOD 750 at superior and nasal, TIA 500 at superior, and inferior and TIA 750 at superior and nasal, and ARA 500 or 750 at superior and inferior with internal fixation lamp were greater and the pupil diameter was significantly (all P < 0.05, paired t test) smaller than when measured without fixation lamp. Internal fixation lamp of the anterior segment OCT makes the pupil constrict and angle wider. When using AS-OCT with usual setting with internal fixation lamp on with eyes in which the anterior chamber angle is narrow but open, it is recommended that the internal fixation lamp be turned off to ensure a clear indication as to whether the angle is open or closed in the dark.

  6. [Effects of nootropic agents on visual functions and lacrimal antioxidative activity in patients with primary open-angle glaucoma].

    PubMed

    Davydova, N G; Kuznetsova, T P; Borisova, S A; Abdulkadyrova, M Zh

    2006-01-01

    The paper presents the results of an investigation of the effect of the nootropic agents pantogam and nooclerine on visual functions in patients with primary open-angle glaucoma. These agents have been found to have a beneficial effect on the functional activity of the retina and optic nerve, light sensitivity, hemo- and hydrodynamics of the eye.

  7. Evaluation of Glaucoma Progression in Large-Scale Clinical Data: The Japanese Archive of Multicentral Databases in Glaucoma (JAMDIG).

    PubMed

    Fujino, Yuri; Asaoka, Ryo; Murata, Hiroshi; Miki, Atsuya; Tanito, Masaki; Mizoue, Shiro; Mori, Kazuhiko; Suzuki, Katsuyoshi; Yamashita, Takehiro; Kashiwagi, Kenji; Shoji, Nobuyuki

    2016-04-01

    To develop a large-scale real clinical database of glaucoma (Japanese Archive of Multicentral Databases in Glaucoma: JAMDIG) and to investigate the effect of treatment. The study included a total of 1348 eyes of 805 primary open-angle glaucoma patients with 10 visual fields (VFs) measured with 24-2 or 30-2 Humphrey Field Analyzer (HFA) and intraocular pressure (IOP) records in 10 institutes in Japan. Those with 10 reliable VFs were further identified (638 eyes of 417 patients). Mean total deviation (mTD) of the 52 test points in the 24-2 HFA VF was calculated, and the relationship between mTD progression rate and seven variables (age, mTD of baseline VF, average IOP, standard deviation (SD) of IOP, previous argon/selective laser trabeculoplasties (ALT/SLT), previous trabeculectomy, and previous trabeculotomy) was analyzed. The mTD in the initial VF was -6.9 ± 6.2 dB and the mTD progression rate was -0.26 ± 0.46 dB/year. Mean IOP during the follow-up period was 13.5 ± 2.2 mm Hg. Age and SD of IOP were related to mTD progression rate. However, in eyes with average IOP below 15 and also 13 mm Hg, only age and baseline VF mTD were related to mTD progression rate. Age and the degree of VF damage were related to future progression. Average IOP was not related to the progression rate; however, fluctuation of IOP was associated with faster progression, although this was not the case when average IOP was below 15 mm Hg.

  8. Molecular Dynamics Simulations of Ligand-Induced Flap Conformational Changes in Cathepsin-D-A Comparative Study.

    PubMed

    Arodola, Olayide A; Soliman, Mahmoud E S

    2016-11-01

    The flap region in aspartic proteases is a unique structural feature to this class of enzymes, and found to have a profound impact on protein overall structure, function, and dynamics. Understanding the structure and dynamic behavior of the flap regions is crucial in the design of selective inhibitors against aspartic proteases. Cathepsin-D, an aspartic protease enzyme, has been implicated in a long list of degenerative diseases as well as breast cancer progression. Presented herein, for the first time, is a comprehensive description of the conformational flap dynamics of cathepsin-D using a comparative 50 ns "multiple" molecular dynamics simulations. Diverse collective metrics were proposed to accurately define flap dynamics. These are distance d1 between the flap tips residues (Gly79 and Met301); dihedral angle ϕ; in addition to TriCα angles Gly79-Asp33-Asp223, θ1 , and Gly79-Asp223-Met301, θ2 . The maximum distance attained throughout the simulation was 17.42 and 11.47 Å for apo and bound cathepsin-D, respectively, while the minimum distance observed was 8.75 and 6.32 Å for apo and bound cathepsin-D, respectively. The movement of the flap as well as the twist of the active pocket can properly be explained by measuring the angle, θ1 , between Gly79-Asp33-Met301 and correlating it with the distance Cα of the flap tip residues. The asymmetrical opening of the binding cavity was best described by the large shift of -6.26° to +20.94° in the dihedral angle, ϕ, corresponding to the full opening of the flap at a range of 31-33 ns. A wide-range of post-dynamic analyses was also applied in this report to supplement our findings. We believe that this report would augment current efforts in designing potent structure-based inhibitors against cathepsin-D in the treatment of breast cancer and other degenerative diseases. J. Cell. Biochem. 117: 2643-2657, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. OpenMDAO Framework Status

    NASA Technical Reports Server (NTRS)

    Naiman, Cynthia Gutierrez

    2010-01-01

    Advancing and exploring the science of Multidisciplinary Analysis & Optimization (MDAO) capabilities are high-level goals in the Fundamental Aeronautics Program s Subsonic Fixed Wing (SFW) project. The OpenMDAO team has made significant progress toward completing the Alpha OpenMDAO deliverable due in September 2010. Included in the presentation are: details of progress on developing the OpenMDAO framework, example usage of OpenMDAO, technology transfer plans, near term plans, progress toward establishing partnerships with external parties, and discussion of additional potential collaborations.

  10. The relationship between the fistula tract and the facial nerve in type II first branchial cleft anomalies.

    PubMed

    Ertas, Burak; Gunaydin, Rıza Onder; Unal, Omer Faruk

    2015-04-01

    To share our experience involving seven patients with type II first branchial cleft anomalies (hereafter, type II anomalies), to determine whether the location of the external fistula openings of the anomalies are associated with the location of the facial nerve tract, and elucidate the relationship between the location of the fistula opening and the facial nerve. The medical records of seven patients who underwent surgery from 2005 to 2013 for type II anomalies were retrospectively examined. The relationship between the fistula opening and the facial nerve was evaluated in each patient with respect to whether the fistula opening was superior or inferior to the mandibular angle. All patients underwent partial parotidectomy, facial nerve exposure, and total excision of the mass together with connection of a small cuff of the external auditory canal skin to the fistula tract. The fistula tracts were located medially to the facial nerve in two patients, and both fistulae had openings inferior to the mandibular angle. The fistula tracts were located laterally to the facial nerve in the remaining five patients: one patient had no external opening, one had an opening inferior to the mandibular angle, and the remaining three had openings superior to the mandibular angle. Because type II anomalies are rare, their diagnosis is difficult. Surgery of such lesions is challenging and associated with a high risk due to their proximity to the facial nerve. We believe that the location of the fistula opening may help to identify the relationship between the anomalous lesion and facial nerve. Studies involving larger series of cases are needed to confirm our hypothesis; however, because of the rarity of this specific anomaly, it will not be easy to compile a large number of cases. We believe that our study will encourage further investigation on this subject. Copyright © 2014. Published by Elsevier Ireland Ltd.

  11. The correlation between calcaneal valgus angle and asymmetrical thoracic-lumbar rotation angles in patients with adolescent scoliosis.

    PubMed

    Park, Jaeyong; Lee, Sang Gil; Bae, Jongjin; Lee, Jung Chul

    2015-12-01

    [Purpose] This study aimed to provide a predictable evaluation method for the progression of scoliosis in adolescents based on quick and reliable measurements using the naked eye, such as the calcaneal valgus angle of the foot, which can be performed at public facilities such as schools. [Subjects and Methods] Idiopathic scoliosis patients with a Cobb's angle of 10° or more (96 females, 22 males) were included in this study. To identify relationships between factors, Pearson's product-moment correlation coefficient was computed. The degree of scoliosis was set as a dependent variable to predict thoracic and lumbar scoliosis using ankle angle and physique factors. Height, weight, and left and right calcaneal valgus angles were set as independent variables; thereafter, multiple regression analysis was performed. This study extracted variables at a significance level (α) of 0.05 by applying a stepwise method, and calculated a regression equation. [Results] Negative correlation (R=-0.266) was shown between lumbar lordosis and asymmetrical lumbar rotation angles. A correlation (R=0.281) was also demonstrated between left calcaneal valgus angles and asymmetrical thoracic rotation angles. [Conclusion] Prediction of scoliosis progress was revealed to be possible through ocular inspection of the calcaneus and Adams forward bending test and the use of a scoliometer.

  12. Comparison of Dimensional Accuracy between Open-Tray and Closed-Tray Implant Impression Technique in 15° Angled Implants

    PubMed Central

    Balouch, F; Jalalian, E; Nikkheslat, M; Ghavamian, R; Toopchi, Sh; Jallalian, F; Jalalian, S

    2013-01-01

    Statement of Problem: Various impression techniques have different effects on the accuracy of final cast dimensions. Meanwhile; there are some controversies about the best technique. Purpose: This study was performed to compare two kinds of implant impression methods (open tray and closed tray) on 15 degree angled implants. Materials and Method: In this experimental study, a steel model with 8 cm in diameter and 3 cm in height were produced with 3 holes devised inside to stabilize 3 implants. The central implant was straight and the other two implants were 15° angled. The two angled implants had 5 cm distance from each other and 3.5 cm from the central implant. Dental stone, high strength (type IV) was used for the main casts. Impression trays were filled with poly ether, and then the two impression techniques (open tray and closed tray) were compared. To evaluate positions of the implants, each cast was analyzed by CMM device in 3 dimensions (x,y,z). Differences in the measurements obtained from final casts and laboratory model were analyzed using t-Test. Results: The obtained results indicated that closed tray impression technique was significantly different in dimensional accuracy when compared with open tray method. Dimensional changes were 129 ± 37μ and 143.5 ± 43.67μ in closed tray and open tray, while coefficient of variation in closed- tray and open tray were reported to be 27.2% and 30.4%, respectively. Conclusion: Closed impression technique had less dimensional changes in comparison with open tray method, so this study suggests that closed tray impression technique is more accurate. PMID:24724130

  13. Making Sense by Measuring Arcs: A Teaching Experiment in Angle Measure

    ERIC Educational Resources Information Center

    Moore, Kevin C.

    2013-01-01

    I discuss a teaching experiment that sought to characterize precalculus students' angle measure understandings. The study's findings indicate that the students initially conceived angle measures in terms of geometric objects. As the study progressed, the students formed more robust understandings of degree and radian measures by constructing an…

  14. Holographic Jet Shapes and their Evolution in Strongly Coupled Plasma

    NASA Astrophysics Data System (ADS)

    Brewer, Jasmine; Rajagopal, Krishna; Sadofyev, Andrey; van der Schee, Wilke

    2017-11-01

    Recently our group analyzed how the probability distribution for the jet opening angle is modified in an ensemble of jets that has propagated through an expanding cooling droplet of plasma [K. Rajagopal, A. V. Sadofyev, W. van der Schee, Phys. Rev. Lett. 116 (2016) 211603]. Each jet in the ensemble is represented holographically by a string in the dual 4+1- dimensional gravitational theory with the distribution of initial energies and opening angles in the ensemble given by perturbative QCD. In [K. Rajagopal, A. V. Sadofyev, W. van der Schee, Phys. Rev. Lett. 116 (2016) 211603], the full string dynamics were approximated by assuming that the string moves at the speed of light. We are now able to analyze the full string dynamics for a range of possible initial conditions, giving us access to the dynamics of holographic jets just after their creation. The nullification timescale and the features of the string when it has nullified are all results of the string evolution. This emboldens us to analyze the full jet shape modification, rather than just the opening angle modification of each jet in the ensemble as in [K. Rajagopal, A. V. Sadofyev, W. van der Schee, Phys. Rev. Lett. 116 (2016) 211603]. We find the result that the jet shape scales with the opening angle at any particular energy. We construct an ensemble of dijets with energies and energy asymmetry distributions taken from events in proton-proton collisions, opening angle distribution as in [K. Rajagopal, A. V. Sadofyev, W. van der Schee, Phys. Rev. Lett. 116 (2016) 211603], and jet shape taken from proton-proton collisions and scaled according to our result. We study how these observables are modified after we send the ensemble of dijets through the strongly-coupled plasma.

  15. Effect of proprioceptive training on foot posture, lower limb alignment, and knee adduction moment in patients with degenerative knee osteoarthritis: a randomized controlled trial

    PubMed Central

    Cho, Yumi; Kim, Minkyu; Lee, Wanhee

    2015-01-01

    [Purpose] The purpose of this study was to determine the effect of proprioceptive training on foot progression angle, weight-bearing ratio, and knee adduction moment in patients with degenerative osteoarthritis of the knee. [Subjects] The subjects were 37 patients diagnosed with Kellgren-Lawrence grade 2 or 3 degenerative knee osteoarthritis. They were randomly allocated to three groups: a proprioceptive training group (PT group), quadriceps strengthening group (QS group), and control group. [Methods] The study parameters of the three groups were compared before and after a 12-week training period. Therapeutic exercises were performed twice per week for 12 weeks. Outcomes included the foot progression angle, weight-bearing ratio, and knee adduction moment. [Results] First, a significant difference in the foot progression angle was observed among the groups, significantly increasing in the PTG compared with the CG. Second, a significant difference in the weight-bearing ratio was observed among the groups, significantly increasing in the PTG compared with the CG. Third, a significant difference in the first peak knee adduction moment was observed among the groups, significantly decreasing in the PTG compared with the CG. [Conclusion] The results of the present study indicate that proprioceptive training increased the foot progression angle and weight-bearing ratio and decreased the first peak knee adduction moment. Moreover, incorporating proprioceptive training into a physical therapy exercise program could improve functional ability and delay the progression of degenerative osteoarthritis. PMID:25729170

  16. Using Digital Technology to See Angles from Different Angles. Part 2: Openings and Turns

    ERIC Educational Resources Information Center

    Host, Erin; Baynham, Emily; McMaster, Heather

    2015-01-01

    Ever wondered how to use technology to teach angles? This article follows on from an earlier article published last year, providing a range of ideas for integrating technology and concrete materials with the teaching of angle concepts. The authors also provide a comprehensive list of free online games and learning objects that can be used to teach…

  17. A method to detect progression of glaucoma using the multifocal visual evoked potential technique

    PubMed Central

    Wangsupadilok, Boonchai; Kanadani, Fabio N.; Grippo, Tomas M.; Liebmann, Jeffrey M.; Ritch, Robert; Hood, Donald C.

    2010-01-01

    Purpose To describe a method for monitoring progression of glaucoma using the multifocal visual evoked potential (mfVEP) technique. Methods Eighty-seven patients diagnosed with open-angle glaucoma were divided into two groups. Group I, comprised 43 patients who had a repeat mfVEP test within 50 days (mean 0.9 ± 0.5 months), and group II, 44 patients who had a repeat test after at least 6 months (mean 20.7 ± 9.7 months). Monocular mfVEPs were obtained using a 60-sector pattern reversal dartboard display. Monocular and interocular analyses were performed. Data from the two visits were compared. The total number of abnormal test points with P < 5% within the visual field (total scores) and number of abnormal test points within a cluster (cluster size) were calculated. Data for group I provided a measure of test–retest variability independent of disease progression. Data for group II provided a possible measure of progression. Results The difference in the total scores for group II between visit 1 and visit 2 for the interocular and monocular comparison was significant (P < 0.05) as was the difference in cluster size for the interocular comparison (P < 0.05). Group I did not show a significant change in either total score or cluster size. Conclusion The change in the total score and cluster size over time provides a possible method for assessing progression of glaucoma with the mfVEP technique. PMID:18830654

  18. Early Detection of Progressive Adolescent Idiopathic Scoliosis: A Severity Index.

    PubMed

    Skalli, Wafa; Vergari, Claudio; Ebermeyer, Eric; Courtois, Isabelle; Drevelle, Xavier; Kohler, Remi; Abelin-Genevois, Kariman; Dubousset, Jean

    2017-06-01

    Early detection of progressive adolescent idiopathic scoliosis (AIS) was assessed based on 3D quantification of the deformity. Based on 3D quantitative description of scoliosis curves, the aim is to assess a specific phenotype that could be an early detectable severity index for progressive AIS. Early detection of progressive scoliosis is important for adapted treatment to limit progression. However, progression risk assessment is mainly based on the follow up, waiting for signs of rapid progression that generally occur during the growth peak. Sixty-five mild scoliosis (16 boys, 49 girls, Cobb Angle between 10 and 20°) with a Risser between 0 and 2 were followed from their first examination until a decision was made by the clinician, either considering the spine as stable at the end of growth (26 patients) or planning to brace because of progression (39 patients). Calibrated biplanar x-rays were performed and 3D reconstructions of the spine allowed calculating six local parameters related to main curve deformity. For progressive curve 3D phenotype assessment, data were compared with those previously assessed for 30 severe scoliosis (Cobb Angle > 35°), 17 scoliosis before brace (Cobb Angle > 29°) and 53 spines of nonscoliosis subjects. A predictive discriminant analysis was performed to assess similarity of mild scoliosis curves either to those of scoliosis or nonscoliosis spines, yielding a severity index (S-index). S-index value at first examination was compared with clinical outcome. At the first exam, 53 out of 65 predictions (82%) were in agreement with actual clinical outcome. Approximately, 89% of the curves that were predicted as progressive proved accurate. Although still requiring large scale validation, results are promising for early detection of progressive curves. 2.

  19. Minimally Invasive and Open Distal Chevron Osteotomy for Mild to Moderate Hallux Valgus.

    PubMed

    Brogan, Kit; Lindisfarne, Edward; Akehurst, Harold; Farook, Usama; Shrier, Will; Palmer, Simon

    2016-11-01

    Minimally invasive surgical (MIS) techniques are increasingly being used in foot and ankle surgery but it is important that they are adopted only once they have been shown to be equivalent or superior to open techniques. We believe that the main advantages of MIS are found in the early postoperative period, but in order to adopt it as a technique longer-term studies are required. The aim of this study was to compare the 2-year outcomes of a third-generation MIS distal chevron osteotomy with a comparable traditional open distal chevron osteotomy for mild-moderate hallux valgus. Our null hypothesis was that the 2 techniques would yield equivalent clinical and radiographic results at 2 years. This was a retrospective cohort study. Eighty-one consecutive feet (49 MIS and 32 open distal chevron osteotomies) were followed up for a minimum 24 months (range 24-58). All patients were clinically assessed using the Manchester-Oxford Foot Questionnaire. Radiographic measures included hallux valgus angle, the intermetatarsal angle, hallux interphalangeal angle, metatarsal phalangeal joint angle, distal metatarsal articular angle, tibial sesamoid position, shape of the first metatarsal head, and plantar offset. Statistical analysis was done using Student t test or Wilcoxon rank-sum test for continuous data and Pearson chi-square test for categorical data. Clinical and radiologic postoperative scores in all domains were substantially improved in both groups (P < .001), but there was no statistically significant difference in improvement of any domain between open and MIS groups (P > .05). There were no significant differences in complications between the 2 groups ( > .5). The midterm results of this third-generation technique show that it was a safe procedure with good clinical outcomes and comparable to traditional open techniques for symptomatic mild-moderate hallux valgus. Level III, retrospective comparative study. © The Author(s) 2016.

  20. Angle stability and outflow in dual blade ab interno trabeculectomy with active versus passive chamber management

    PubMed Central

    Wang, Chao; Dang, Yalong; Waxman, Susannah; Xia, Xiaobo; Weinreb, Robert N.

    2017-01-01

    Purpose To compare intraoperative angle stability and postoperative outflow of two ab interno trabeculectomy devices that excise the trabecular meshwork with or without active aspiration and irrigation. We hypothesized that anterior segment optical coherence tomography (AS-OCT) allows for a quantitative comparison of intraoperative angle stability in a microincisional glaucoma surgery (MIGS) pig eye training model. Methods Twelve freshly enucleated porcine eyes were measured with AS-OCT at baseline, at the beginning of the procedure and at its conclusion to determine the anterior chamber depth (ACD) and the nasal angle α in degrees. The right and left eye of pairs were randomly assigned to an active dual blade goniectome (aDBG) and a passive dual blade goniectome (pDBG) group, respectively. The aDBG had irrigation and aspiration ports while the pDBG required surgery under viscoelastic. We performed the procedures using our MIGS training system with a standard, motorized ophthalmic operating microscope. We estimated outflow by obtaining canalograms with fluorescent spheres. Results In aDBG, the nasal angle remained wide open during the procedure at above 90° and did not change towards the end (100±10%, p = 0.9). In contrast, in pDBG, ACD decreased by 51±19% to 21% below baseline (p<0.01) while the angle progressively narrowed by 40±12% (p<0.001). Canalograms showed a similar extent of access to the outflow tract with the aDBG and the pDBG (p = 0.513). The average increase for the aDBG in the superonasal and inferonasal quadrants was between 27 to 31% and for the pDBG between 15 to 18%. Conclusion AS-OCT demonstrated that active irrigation and aspiration improved anterior chamber maintenance and ease of handling with the aDBG in this MIGS training model. The immediate postoperative outflow was equally good with both devices. PMID:28486513

  1. The Prevalence of Age-Related Eye Diseases and Visual Impairment in Aging: Current Estimates

    PubMed Central

    Klein, Ronald; Klein, Barbara E. K.

    2013-01-01

    Purpose. To examine prevalence of five age-related eye conditions (age-related cataract, AMD, open-angle glaucoma, diabetic retinopathy [DR], and visual impairment) in the United States. Methods. Review of published scientific articles and unpublished research findings. Results. Cataract, AMD, open-angle glaucoma, DR, and visual impairment prevalences are high in four different studies of these conditions, especially in people over 75 years of age. There are disparities among racial/ethnic groups with higher age-specific prevalence of DR, open-angle glaucoma, and visual impairment in Hispanics and blacks compared with whites, higher prevalence of age-related cataract in whites compared with blacks, and higher prevalence of late AMD in whites compared with Hispanics and blacks. The estimates are based on old data and do not reflect recent changes in the distribution of age and race/ethnicity in the United States population. There are no epidemiologic estimates of prevalence for many visually-impairing conditions. Conclusions. Ongoing prevalence surveys designed to provide reliable estimates of visual impairment, AMD, age-related cataract, open-angle glaucoma, and DR are needed. It is important to collect objective data on these and other conditions that affect vision and quality of life in order to plan for health care needs and identify areas for further research. PMID:24335069

  2. Open-angle glaucoma in the Petit Basset Griffon Vendeen.

    PubMed

    Bedford, Peter G C

    2017-03-01

    To report the prevalence and clinical characteristics of an open-angle glaucoma in Petit Basset Griffon Vendeen (PBGV) dogs in the United Kingdom (UK). At breed society clinics extending over a 6-year period, 366 dogs of varying ages and both sexes were clinically examined for signs of glaucoma using slit-lamp biomicroscopy, indirect and direct ophthalmoscopy, tonometry, and gonioscopy. The prevalence of glaucoma was 10.4% (38 dogs). Clinical signs of the disease presented from 3 years of age onwards, the commonest initial feature being the elevation of intraocular pressure (IOP) in 15 dogs (39.4%). In addition to elevated IOP, another 13 dogs (34.2%) presented with other features of glaucoma, some with lens subluxation and globe enlargement and all with possible or known vision defects. In the remaining 10 dogs (26.3%), phacodonesis or lens subluxation was observed before subsequent elevation of IOP. High prevalence and similarity to the primary open-angle glaucoma (POAG) seen in the Beagle and Elkhound breeds indicate that an open-angle glaucoma is present in the PBGV in the UK and that this disease may be genetically determined in this breed. Although increased IOP is the commonest early diagnostic feature, lens instability prior to an increase in IOP may be part of the clinical picture. © 2016 American College of Veterinary Ophthalmologists.

  3. Economic impact of primary open-angle glaucoma in Australia.

    PubMed

    Dirani, Mohamed; Crowston, Jonathan G; Taylor, Penny S; Moore, Peter T; Rogers, Sophie; Pezzullo, M Lynne; Keeffe, Jill E; Taylor, Hugh R

    2011-01-01

    Glaucoma is the World's leading cause of irreversible blindness, and poses serious public health and economic concerns.   Review. Published randomized trials and population-based studies since 1985. We report the economic impact of primary open-angle glaucoma and model the effect of changes in detection rates and management strategies. The cost-effectiveness of different interventions to prevent vision loss from primary open-angle glaucoma was measured in terms of financial cost (Australian dollars) and disability-adjusted life years. The prevalence of glaucoma in Australia is expected to increase from 208 000 in 2005 to 379 000 in 2025 because of the aging population. Health system costs over the same time period are estimated to increase from $AU355 million to $AU784 million. Total costs (health system costs, indirect costs and costs of loss of well-being) will increase from $AU1.9 billion to $AU4.3 billion in Australia. Primary open-angle glaucoma poses a significant economic burden, which will increase substantially by 2025. This dynamic model provides a valuable tool for ongoing policy formulation and determining the economic impact of interventions to better prevent visual impairment and blindness from glaucoma. © 2011 The Authors. Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists.

  4. Investigation of Blade Angle of an Open Cross-Flow Runner

    NASA Astrophysics Data System (ADS)

    Katayama, Yusuke; Iio, Shouichiro; Veerapun, Salisa; Uchiyama, Tomomi

    2015-04-01

    The aim of this study was to develop a nano-hydraulic turbine utilizing drop structure in irrigation channels or industrial waterways. This study was focused on an open-type cross-flow turbine without any attached equipment for cost reduction and easy maintenance. In this study, the authors used an artificial indoor waterfall as lab model. Test runner which is a simple structure of 20 circular arc-shaped blades sandwiched by two circular plates was used The optimum inlet blade angle and the relationship between the power performance and the flow rate approaching theoretically and experimentally were investigated. As a result, the optimum inlet blade angle due to the flow rate was changed. Additionally, allocation rate of power output in 1st stage and 2nd stage is changed by the blade inlet angle.

  5. Differences in iris thickness among African Americans, Caucasian Americans, Hispanic Americans, Chinese Americans, and Filipino-Americans.

    PubMed

    Lee, Roland Y; Huang, Guofu; Porco, Travis C; Chen, Yi-Chun; He, Mingguang; Lin, Shan C

    2013-12-01

    To evaluate the capability of iris thickness parameters to explain the difference in primary angle-closure glaucoma prevalence among the different racial groups. In this prospective study, 436 patients with open and narrow angles that met inclusion criteria were consecutively recruited from the UCSF general ophthalmology and glaucoma clinics to receive anterior segment optical coherence tomography imaging under standardized dark conditions. Images from 11 patients were removed due to poor visibility of the scleral spurs and the remaining images were analyzed using the Zhongshan Angle Assessment Program to assess the following measurements for the nasal and temporal angle of the anterior chamber: iris thickness at 750 and 2000 μm from the scleral spurs and the maximum iris thickness at middle one third of the iris. Iris thickness parameters were compared among and within the following 5 different racial groups: African Americans, Caucasian Americans, Hispanic Americans, Chinese Americans, and Filipino-Americans. In comparing iris parameters among the open-angle racial groups, significant differences were found for nasal iris thickness at 750 and 2000 μm from the scleral spurs in which Chinese Americans displayed the highest mean value (P=0.01, P<0.0001). Among the narrow-angle racial groups, significant difference was found for nasal iris thickness at 2000 μm from the scleral in which Chinese Americans showed the highest mean value (P<0.0001). Significant difference was also found for temporal maximum iris thickness at middle one third of the iris in which African Americans exhibited the highest mean value (P=0.021). Iris thickness was modeled as a function of angle status using linear mixed-effects regression, adjusting for age, sex, pupil diameter, spherical equivalent, ethnicity, and the use of both eyes in patients. The iris thickness difference between the narrow-angle and open-angle groups was significant (P=0.0007). Racial groups that historically showed higher prevalence of primary angle-closure glaucoma possess thicker irides.

  6. Pilot Study of the Effects of Ambient Light Level Variation on Spectral Domain Anterior Segment OCT-Derived Angle Metrics in Caucasians versus Asians.

    PubMed

    Dastiridou, Anna; Marion, Kenneth; Niemeyer, Moritz; Francis, Brian; Sadda, Srinivas; Chopra, Vikas

    2018-04-11

    To investigate the effects of ambient light level variation on spectral domain anterior segment optical coherence tomography (SD-ΟCT)-derived anterior chamber angle metrics in Caucasians versus Asians. Caucasian (n = 24) and Asian participants of Chinese ancestry (n = 24) with open angles on gonioscopy had one eye imaged twice at five strictly controlled, ambient light levels. Ethnicity was self-reported. Light levels were strictly controlled using a light meter at 1.0, 0.75, 0.5, 0.25, and 0 foot candle illumination levels. SD-OCT 5-line raster scans at the inferior 270° irido-corneal angle were measured by two trained, masked graders from the Doheny Image Reading Center using customized Image-J software. Schwalbe's line-angle opening distance (SL-AOD) and SL-trabecular iris space area (SL-TISA) in different light meter readings (LMRs) between the two groups were compared. Baseline light SL-AOD and SL-TISA measured 0.464 ± 0.115mm/0.351 ± 0.110mm 2 and 0.344 ± 0.118mm/0.257 ± 0.092mm 2 , respectively, in the Caucasian and the Asian group. SL-AOD and SL-TISA in each LMR were significantly larger in the Caucasian group compared to the Asian group (p < 0.05). Despite this difference in angle size between the groups, there were no statistically significant differences in the degree of change in angle parameters from light to dark (% changes in SL-AOD or SL-TISA between the two groups were statistically similar with all p-values >0.3). SL-based angle dimensions using SD-OCT are sensitive to changes in ambient illumination in participants with Caucasian and Asian ancestry. Although Caucasian eyes had larger baseline angle opening under bright light conditions, the light-to-dark change in angle dimensions was similar in the two groups.

  7. Novel Automated Approach to Predict the Outcome of Laser Peripheral Iridotomy for Primary Angle Closure Suspect Eyes Using Anterior Segment Optical Coherence Tomography.

    PubMed

    Koh, Victor; Swamidoss, Issac Niwas; Aquino, Maria Cecilia D; Chew, Paul T; Sng, Chelvin

    2018-04-27

    Develop an algorithm to predict the success of laser peripheral iridotomy (LPI) in primary angle closure suspect (PACS), using pre-treatment anterior segment optical coherence tomography (ASOCT) scans. A total of 116 eyes with PACS underwent LPI and time-domain ASOCT scans (temporal and nasal cuts) were performed before and 1 month after LPI. All the post-treatment scans were classified to one of the following categories: (a) both angles open, (b) one of two angles open and (c) both angles closed. After LPI, success is defined as one or more angles changed from close to open. In this proposed method, the pre and post-LPI ASOCT scans were registered at the corresponding angles based on similarities between the respective local descriptor features and random sample consensus technique was used to identify the largest consensus set of correspondences between the pre and post-LPI ASOCT scans. Subsequently, features such as correlation co-efficient (CC) and structural similarity index (SSIM) were extracted and correlated with the success of LPI. We included 116 eyes and 91 (78.44%) eyes fulfilled the criteria for success after LPI. Using the CC and SSIM index scores from this training set of ASOCT images, our algorithm showed that the success of LPI in eyes with narrow angles can be predicted with 89.7% accuracy, specificity of 95.2% and sensitivity of 36.4% based on pre-LPI ASOCT scans only. Using pre-LPI ASOCT scans, our proposed algorithm showed good accuracy in predicting the success of LPI for PACS eyes. This fully-automated algorithm could aid decision making in offering LPI as a prophylactic treatment for PACS.

  8. Passive rejection of heat from an isotope heat source through an open door

    NASA Technical Reports Server (NTRS)

    Burns, R. K.

    1971-01-01

    The isotope heat-source design for a Brayton power system includes a door in the thermal insulation through which the heat can be passively rejected to space when the power system is not operating. The results of an analysis to predict the heat-source surface temperature and the heat-source heat-exchanger temperature during passive heat rejection as a function of insulation door opening angle are presented. They show that for a door opening angle greater than 20 deg, the temperatures are less than the steady-state temperatures during power system operation.

  9. Development and initial validation of the Classification of Early-Onset Scoliosis (C-EOS).

    PubMed

    Williams, Brendan A; Matsumoto, Hiroko; McCalla, Daren J; Akbarnia, Behrooz A; Blakemore, Laurel C; Betz, Randal R; Flynn, John M; Johnston, Charles E; McCarthy, Richard E; Roye, David P; Skaggs, David L; Smith, John T; Snyder, Brian D; Sponseller, Paul D; Sturm, Peter F; Thompson, George H; Yazici, Muharrem; Vitale, Michael G

    2014-08-20

    Early-onset scoliosis is a heterogeneous condition, with highly variable manifestations and natural history. No standardized classification system exists to describe and group patients, to guide optimal care, or to prognosticate outcomes within this population. A classification system for early-onset scoliosis is thus a necessary prerequisite to the timely evolution of care of these patients. Fifteen experienced surgeons participated in a nominal group technique designed to achieve a consensus-based classification system for early-onset scoliosis. A comprehensive list of factors important in managing early-onset scoliosis was generated using a standardized literature review, semi-structured interviews, and open forum discussion. Three group meetings and two rounds of surveying guided the selection of classification components, subgroupings, and cut-points. Initial validation of the system was conducted using an interobserver reliability assessment based on the classification of a series of thirty cases. Nominal group technique was used to identify three core variables (major curve angle, etiology, and kyphosis) with high group content validity scores. Age and curve progression ranked slightly lower. Participants evaluated the cases of thirty patients with early-onset scoliosis for reliability testing. The mean kappa value for etiology (0.64) was substantial, while the mean kappa values for major curve angle (0.95) and kyphosis (0.93) indicated almost perfect agreement. The final classification consisted of a continuous age prefix, etiology (congenital or structural, neuromuscular, syndromic, and idiopathic), major curve angle (1, 2, 3, or 4), and kyphosis (-, N, or +) variables, and an optional progression modifier (P0, P1, or P2). Utilizing formal consensus-building methods in a large group of surgeons experienced in treating early-onset scoliosis, a novel classification system for early-onset scoliosis was developed with all core components demonstrating substantial to excellent interobserver reliability. This classification system will serve as a foundation to guide ongoing research efforts and standardize communication in the clinical setting. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.

  10. Iridotomy to slow progression of angle-closure glaucoma

    PubMed Central

    Le, Jimmy T; Rouse, Benjamin; Gazzard, Gus

    2016-01-01

    This is the protocol for a review and there is no abstract. The objectives are as follows: The primary objective is to assess the role of iridotomy-compared with observation-in the prevention of visual field loss for individuals who have primary angle closure or primary angle-closure glaucoma in at least one eye. We will also examine the role of iridotomy in the prevention of elevated intraocular pressure (IOP) in individuals with narrow angles (primary angle-closure suspect) in at least one eye. PMID:27551238

  11. Changes in anterior segment morphology in response to illumination and after laser iridotomy in Asian eyes: an anterior segment OCT study

    PubMed Central

    See, Jovina L S; Chew, Paul T K; Smith, Scott D; Nolan, Winifred P; Chan, Yiong‐Huak; Huang, David; Zheng, Ce; Foster, Paul J; Aung, Tin; Friedman, David S

    2007-01-01

    Aim Using the anterior segment optical coherence tomography (AS‐OCT) to quantify changes in anterior segment morphology going from light to dark and following laser iridotomy (LI). Methods Prospective observational study. 17 consecutive subjects without peripheral anterior synechiae undergoing LI were evaluated using gonioscopy and AS‐OCT. Angle configuration including angle opening distance (AOD) at 500 microns anterior to the scleral spur, AOD500, trabecular‐iris space area up to 750 microns from the scleral spur, TISA750 and the increase in angle opening going from dark to light conditions was determined. Results Both mean AOD500 and TISA750 increased nearly threefold going from dark to light. Both also significantly increased following LI (p<0.001) as did gonioscopic grading of the angle in all quadrants (p<0.001, McNemar's test). Angles were more than twice as wide on average in the dark after LI than before LI (p<0.05). Both the mean absolute change and the mean proportionate change in AOD500 and TISA750 when going from light to dark were greater after LI than before (p<0.05). Conclusion Increased illumination as well as LI resulted in significant widening of the anterior chamber angle. AS‐OCT (which does not require a water bath and can be performed with the patient at the slit lamp) identified similar magnitude changes as those previously reported using ultrasound biomicroscopy (UBM). Furthermore, the angle appears to open more both in absolute terms and and proportionate terms in response to illumination after LI. PMID:17504852

  12. Hidden One-Dimensional Electronic Structure of η-Mo_4O_11

    NASA Astrophysics Data System (ADS)

    Gweon, G.-H.; Mo, S.-K.; Allen, J. W.; Höchst, H.; Sarrao, J. L.; Fisk, Z.

    2002-03-01

    η-Mo_4O_11 is a layered metal that undergoes two charge density wave (CDW) transitions at 109 K and 30 K, and is unique in showing a bulk quantum Hall effect. Research so far indicates that this material has a ``hidden one-dimensional'' (hidden-1d) Fermi surface (FS) in the normal state (T > 109 K), whose nesting property drives the 109 K CDW formation. Here, we directly confirm this picture by angle resolved photoemission spectroscopy (ARPES). We also observe a gap opening associated with the 109 K transition. Most interesting, this material shows the same ARPES line shape anomalies that suggest electron fractionalization in other hidden-1d materials like NaMo_6O_17 and KMo_6O_17. Studies of the 30 K transition are in progress.

  13. Quasiparticle self-consistent GW study of cuprates: electronic structure, model parameters, and the two-band theory for Tc

    PubMed Central

    Jang, Seung Woo; Kotani, Takao; Kino, Hiori; Kuroki, Kazuhiko; Han, Myung Joon

    2015-01-01

    Despite decades of progress, an understanding of unconventional superconductivity still remains elusive. An important open question is about the material dependence of the superconducting properties. Using the quasiparticle self-consistent GW method, we re-examine the electronic structure of copper oxide high-Tc materials. We show that QSGW captures several important features, distinctive from the conventional LDA results. The energy level splitting between and is significantly enlarged and the van Hove singularity point is lowered. The calculated results compare better than LDA with recent experimental results from resonant inelastic xray scattering and angle resolved photoemission experiments. This agreement with the experiments supports the previously suggested two-band theory for the material dependence of the superconducting transition temperature, Tc. PMID:26206417

  14. Longitudinal changes in the visual field and optic disc in glaucoma.

    PubMed

    Artes, Paul H; Chauhan, Balwantray C

    2005-05-01

    The nature and mode of functional and structural progression in open-angle glaucoma is a subject of considerable debate in the literature. While there is a traditionally held viewpoint that optic disc and/or nerve fibre layer changes precede visual field changes, there is surprisingly little published evidence from well-controlled prospective studies in this area, specifically with modern perimetric and imaging techniques. In this paper, we report on clinical data from both glaucoma patients and normal controls collected prospectively over several years, to address the relationship between visual field and optic disc changes in glaucoma using standard automated perimetry (SAP), high-pass resolution perimetry (HRP) and confocal scanning laser tomography (CSLT). We use several methods of analysis of longitudinal data and describe a new technique called "evidence of change" analysis which facilitates comparison between different tests. We demonstrate that current clinical indicators of visual function (SAP and HRP) and measures of optic disc structure (CSLT) provide largely independent measures of progression. We discuss the reasons for these findings as well as several methodological issues that pose challenges to elucidating the true structure-function relationship in glaucoma.

  15. Linkage studies in primary open angle glaucoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Avramopoulos, D.; Grigoriadu, M.; Kitsos, G.

    1994-09-01

    Glaucoma is a leading cause of blindness worldwide. The majority of glaucoma is associated with an open, normal appearing anterior chamber angle and is termed primary open angle glaucoma (POAG, MIM 137760). It is characterized by elevated intraocular pressure and onset in middle age or later. A subset of POAG with juvenile onset has recently been linked to chromosome 1q in two families with autosomal dominant inheritance. Eleven pedigrees with autosomal dominant POG (non-juvenile-onset) have been identified in Epirus, Greece. In the present study DNA samples have been collected from 50 individuals from one large pedigree, including 12 affected individuals.more » Preliminary results of linkage analysis with chromosome 1 microsatellites using the computer program package LINKAGE Version 5.1 showed no linkage with the markers previously linked to juvenile-onset POAG. Further linkage analysis is being pursued, and the results will be presented.« less

  16. Visual Disability Among Juvenile Open-angle Glaucoma Patients.

    PubMed

    Gupta, Viney; Ganesan, Vaitheeswaran L; Kumar, Sandip; Chaurasia, Abadh K; Malhotra, Sumit; Gupta, Shikha

    2018-04-01

    Juvenile onset primary open-angle glaucoma (JOAG) unlike adult onset primary open-angle glaucoma presents with high intraocular pressure and diffuse visual field loss, which if left untreated leads to severe visual disability. The study aimed to evaluate the extent of visual disability among JOAG patients presenting to a tertiary eye care facility. Visual acuity and perimetry records of unrelated JOAG patients presenting to our Glaucoma facility were analyzed. Low vision and blindness was categorized by the WHO criteria and percentage impairment was calculated as per the guidelines provided by the American Medical Association (AMA). Fifty-two (15%) of the 348 JOAG patients were bilaterally blind at presentation and 32 (9%) had low vision according to WHO criteria. Ninety JOAG patients (26%) had a visual impairment of 75% or more. Visual disability at presentation among JOAG patients is high. This entails a huge economic burden, given their young age and associated social responsibilities.

  17. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, B; Wong, R; Lam, W

    Purpose: To develop a practical method for routine QA of the MLC of a Tomotherapy unit using ArcCheck. Methods: Two standard test plans were used in this study. One was a helical test, in which the central leaves No. 32 and 33 opened simultaneously for 277.8ms at projections centered at 0°, 120° and 240° gantry angles. The other test plan was a static test with the gantry angle set at 0°, 45°, 90° and 135° respectively and leaves No. 32 and 33 opened sequentially for total 20s which was further divided into eleven or ten segments at each beam angle.more » The ArcCheck was isocentrically set up and adjusted for couch sag. Movie files which took a snapshot exposure every 50ms were recorded. The start/stop time of leaf open was decided by the ramp-up/ramp-down of the detectors. Results: The percentage differences between measured and planned leaf open time were calculated to be within 0.5% in all the tests. In static test, if leaves are synchronized perfectly, the sum of the two detectors’ signals after normalization should equal one when the leaves are in transition. Our results showed mean values of 0.982, 0.983, 0.978 and 0.995 at static gantry angle 0°, 45°, 90° and 135° respectively. Conclusion: A method for estimating the Tomotherapy binary MLC leaf open time using ArcCheck is proposed and proved to be precise enough to verify the planned leaf open time as small as 277.8ms. This method also makes the observation and quantification of the synchronization of leaves possible.« less

  18. Experimental assessment of theory for refraction of sound by a shear layer

    NASA Technical Reports Server (NTRS)

    Schlinker, R. H.; Amiet, R. K.

    1978-01-01

    The refraction angle and amplitude changes associated with sound transmission through a circular, open-jet shear layer were studied in a 0.91 m diameter open jet acoustic research tunnel. Free stream Mach number was varied from 0.1 to 0.4. Good agreement between refraction angle correction theory and experiment was obtained over the test Mach number, frequency and angle measurement range for all on-axis acoustic source locations. For off-axis source positions, good agreement was obtained at a source-to-shear layer separation distance greater than the jet radius. Measureable differences between theory and experiment occurred at a source-to-shear layer separation distance less than one jet radius. A shear layer turbulence scattering experiment was conducted at 90 deg to the open jet axis for the same free stream Mach numbers and axial source locations used in the refraction study. Significant discrete tone spectrum broadening and tone amplitude changes were observed at open jet Mach numbers above 0.2 and at acoustic source frequencies greater than 5 kHz. More severe turbulence scattering was observed for downstream source locations.

  19. Zero-stress states of human pulmonary arteries and veins.

    PubMed

    Huang, W; Yen, R T

    1998-09-01

    The zero-stress states of the pulmonary arteries and veins from order 3 to order 9 were determined in six normal human lungs within 15 h postmortem. The zero-stress state of each vessel was obtained by cutting the vessel transversely into a series of short rings, then cutting each ring radially, which caused the ring to spring open into a sector. Each sector was characterized by its opening angle. The mean opening angle varied between 92 and 163 degrees in the arterial tree and between 89 and 128 degrees in the venous tree. There was a tendency for opening angles to increase as the sizes of the arteries and veins increased. We computed the residual strains based on the experimental measurements and estimated the residual stresses according to Hooke's law. We found that the inner wall of a vessel at the state in which the internal pressure, external pressure, and longitudinal stress are all zero was under compression and the outer wall was in tension, and that the magnitude of compressive stress was greater than the magnitude of tensile stress.

  20. Does hemipelvis structure and position influence acetabulum orientation?

    PubMed

    Musielak, Bartosz; Jóźwiak, Marek; Rychlik, Michał; Chen, Brian Po-Jung; Idzior, Maciej; Grzegorzewski, Andrzej

    2016-03-16

    Although acetabulum orientation is well established anatomically and radiographically, its relation to the innominate bone has rarely been addressed. If explored, it could open the discussion on patomechanisms of such complex disorders as femoroacetabular impingement (FAI). We therefore evaluated the influence of pelvic bone position and structure on acetabular spatial orientation. We describe this relation and its clinical implications. This retrospective study was based on computed tomography scanning of three-dimensional models of 31 consecutive male pelvises (62 acetabulums). All measurements were based on CT spatial reconstruction with the use of highly specialized software (Rhinoceros). Relations between acetabular orientation (inclination, tilt, anteversion angles) and pelvic structure were evaluated. The following parameters were evaluated to assess the pelvic structure: iliac opening angle, iliac tilt angle, interspinous distance (ISD), intertuberous distance (ITD), height of the pelvis (HP), and the ISD/ITD/HP ratio. The linear and nonlinear dependence of the acetabular angles and hemipelvic measurements were examined with Pearson's product - moment correlation and Spearman's rank correlation coefficient. Correlations different from 0 with p < 0.05 were considered statistically significant. Comparison of the axis position with pelvis structure with orientation in the horizontal plane revealed a significant positive correlation between the acetabular anteversion angle and the iliac opening angle (p = 0.041 and 0.008, respectively). In the frontal plane, there was a positive correlation between the acetabular inclination angle and the iliac tilt angle (p = 0.025 and 0.014, respectively) and the acetabular inclination angle and the ISD/ITD/HP ratio (both p = 0.048). There is a significant correlation of the hemipelvic structure and acetabular orientation under anatomic conditions, especially in the frontal and horizontal planes. In the anteroposterior view, the more tilted-down innominate bone causes a more caudally oriented acetabulum axis, whereas in the horizontal view this relation is reversed. This study may serve as a basis for the discussion on the role of the pelvis in common disorders of the hip.

  1. Associations of reading posture, gaze angle and reading distance with myopia and myopic progression.

    PubMed

    Pärssinen, Olavi; Kauppinen, Markku

    2016-12-01

    To study the associations of habitual reading posture, gaze angle in reading and reading distance with myopia and changes in myopia among myopic children. A total of 240 myopic schoolchildren (mean age 10.9 years), with no previous spectacles, were recruited during 1983-1984 to a randomized 3-year clinical trial of bifocal treatment of myopia. Three annual examinations with subjective cycloplegic refraction were conducted for 237-238 subjects. A further examination was conducted at the mean age of 23.2 years for 178 subjects. Habitual reading posture was elicited by questionnaire at study outset. Reading distance was measured with a Clement Clark accommodometer and gaze angle with an angle scale at baseline and all three annual follow-ups. Height was measured by a school nurse. The connections between the variables were studied with the standard statistical methods. Higher myopia was connected with shorter reading distance among girls at follow-ups 2 and 3, but not at the other examinations. The correlation of spherical equivalent with height was non-significant at each follow-up. Myopic progression across the whole follow-up was highest among those who read sitting down at baseline (-3.58 ± 1.75 D) and lowest among those who read face up lying down (-2.35 ± 1.53 D) (p = 0.021). Reading with eyes at a more downward angle was slightly connected with greater myopic progression (r = -0.166, p = 0.028). Reading in a sitting posture at myopia onset predicted the greatest myopic progression to adulthood and reading face up on one's back the lowest. Reading with eyes on turned more downwards was slightly connected with greater myopic progression. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  2. Blood coagulation profiling in patients using optical thromboelastography (OTEG) (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Tripathi, Markandey M.; Tshikudi, Diane M.; Hajjarian, Zeinab; Van Cott, Elizabeth M.; Nadkarni, Seemantini K.

    2016-02-01

    Impaired blood coagulation is often associated with increased postoperative mortality and morbidity in cardiovascular patients. The capability for blood coagulation profiling rapidly at the bedside will enable the timely detection of coagulation defects and open the opportunity for tailoring therapy to correct specific coagulation deficits Optical Thromboelastography (OTEG), is an optical approach to quantify blood coagulation status within minutes using a few drops of whole blood. The goal of the current study is to evaluate the diagnostic accuracy of OTEG for rapid coagulation profiling in patients. In OTEG, temporal laser speckle intensity fluctuations from a drop of clotting blood are measured using a CMOS camera. To quantify coagulation status, the speckle intensity autocorrelation function is measured, the mean square displacement of scattering particles is extracted, and viscoelastic modulus (G), during coagulation is measured via the generalized Stokes-Einstein relation. By quantifying time-resolved changes in G, the coagulation parameters, reaction time (R), clot progression time (K), clot progression rate (Angle), and maximum clot strength (MA) are derived. In this study, the above coagulation parameters were measured using OTEG in 269 patients and compared with standard mechanical Thromboelastography (TEG). Our results showed a strong correlation between OTEG and TEG measurements for all parameters: R-time (R=0.80, p<0.001), clotting time (R=0.78, p<0.001), Angle (R=0.58, p<0.001), and MA (R=0.60, p<0.001). These results demonstrate the unique capability of OTEG for rapid quantification of blood coagulation status to potentially improve clinical capability for identifying impaired coagulation in cardiovascular patients at the point of care.

  3. "The stakes are so high": interviews with progressive journalists reporting on abortion.

    PubMed

    Sisson, Gretchen; Herold, Stephanie; Woodruff, Katie

    2017-12-01

    Because news frames can influence public and policy agendas, proponents of abortion access should be concerned with how this issue is covered in the news. While previous research has examined the content of news on abortion, this analysis explores the process of newsmaking on abortion, examining how journalists understand their role in and experience of covering abortion. We recruited journalists with experience reporting on abortion through listservs for progressive and feminist reporters. Thirty-one participants, with experiences at 75 diverse media outlets, completed in-depth, open-ended interviews. We used grounded theory to code interview transcripts in Dedoose to identity emergent themes. Journalists described many challenges that applied to reporting generally, but that they perceived to be more difficult around abortion: grappling with the meaning of "neutrality" on this issue, finding new angles for articles, and handling editors with varying knowledge of abortion. Over one-third (n=13) of participants mentioned feeling that the stakes were higher around abortion: this urgency and polarization left journalists frustrated by efforts to find new sources or angles on abortion stories. Finally, over 80% (n=28) of participants reported experiencing anti-abortion harassment as a result of their abortion work. The difficulties journalists described when reporting on abortion were often rooted in abortion stigma and the political polarization around the issue. This pattern was true even for reporters who worked to counter abortion stigma through their reporting. Advocates interested in accurate, destigmatizing news frames might work pro-actively to educate editors and increase reporters' access to providers, patients, and advocates. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Association of Baseline Anterior Segment Parameters With the Development of Incident Gonioscopic Angle Closure.

    PubMed

    Nongpiur, Monisha E; Aboobakar, Inas F; Baskaran, Mani; Narayanaswamy, Arun; Sakata, Lisandro M; Wu, Renyi; Atalay, Eray; Friedman, David S; Aung, Tin

    2017-03-01

    Baseline anterior segment imaging parameters associated with incident gonioscopic angle closure, to our knowledge, are unknown. To identify baseline quantitative anterior segment optical coherence tomography parameters associated with the development of incident gonioscopic angle closure after 4 years among participants with gonioscopically open angles at baseline. Three hundred forty-two participants aged 50 years or older were recruited to participate in this prospective, community-based observational study. Participants underwent gonioscopy and anterior segment optical coherence tomography imaging at baseline and after 4 years. Custom image analysis software was used to quantify anterior chamber parameters from anterior segment optical coherence tomography images. Baseline anterior segment optical coherence tomography measurements among participants with gonioscopically open vs closed angles at follow-up. Of the 342 participants, 187 (55%) were women and 297 (87%) were Chinese. The response rate was 62.4%. Forty-nine participants (14.3%) developed gonioscopic angle closure after 4 years. The mean age (SD) at baseline of the 49 participants was 62.9 (8.0) years, 15 (30.6%) were men, and 43 (87.8%) were Chinese. These participants had a smaller baseline angle opening distance at 750 µm (AOD750) (0.15 mm; 95% CI, 0.12-0.18), trabecular iris surface area at 750 µm (0.07 mm2; 95% CI, 0.05-0.08), anterior chamber area (30 mm2; 95% CI, 2.27-3.74), and anterior chamber volume (24.32 mm2; 95% CI, 18.20-30.44) (all P < .001). Baseline iris curvature (-0.08; 95% CI, -0.12 to -0.04) and lens vault (LV) measurements (-0.29 mm; 95% CI, -0.37 to -0.21) were larger among these participants ( all P < .001). A model consisting of the LV and AOD750 measurements explained 38% of the variance in gonioscopic angle closure occurring at 4 years, with LV accounting for 28% of this variance. For every 0.1 mm increase in LV and 0.1 mm decrease in AOD750, the odds of developing gonioscopic angle closure was 1.29 (95% CI, 1.07-1.57) and 3.27 (95% CI, 1.87-5.69), respectively. In terms of per SD change in LV and AOD750, this translates to an odds ratio of 2.14 (95% CI, 2.48-12.34) and 5.53 (95% CI, 1.22-3.77), respectively. A baseline LV cut-off value of >0.56 mm had 64.6% sensitivity and 84.0% specificity for identifying participants who developed angle closure. These findings suggest that smaller AOD750 and larger LV measurements are associated with the development of incident gonioscopic angle closure after 4 years among participants with gonioscopically open angles at baseline.

  5. Detection of Glaucoma Using Image Processing Techniques: A Critique.

    PubMed

    Kumar, B Naveen; Chauhan, R P; Dahiya, Nidhi

    2018-01-01

    The primary objective of this article is to present a summary of different types of image processing methods employed for the detection of glaucoma, a serious eye disease. Glaucoma affects the optic nerve in which retinal ganglion cells become dead, and this leads to loss of vision. The principal cause is the increase in intraocular pressure, which occurs in open-angle and angle-closure glaucoma, the two major types affecting the optic nerve. In the early stages of glaucoma, no perceptible symptoms appear. As the disease progresses, vision starts to become hazy, leading to blindness. Therefore, early detection of glaucoma is needed for prevention. Manual analysis of ophthalmic images is fairly time-consuming and accuracy depends on the expertise of the professionals. Automatic analysis of retinal images is an important tool. Automation aids in the detection, diagnosis, and prevention of risks associated with the disease. Fundus images obtained from a fundus camera have been used for the analysis. Requisite pre-processing techniques have been applied to the image and, depending upon the technique, various classifiers have been used to detect glaucoma. The techniques mentioned in the present review have certain advantages and disadvantages. Based on this study, one can determine which technique provides an optimum result.

  6. The long-term outcomes of four alternative treatment strategies for primary open-angle glaucoma.

    PubMed

    van Gestel, Aukje; Webers, Carroll A; Severens, Johan L; Beckers, Henny J; Jansonius, Nomdo M; Hendrikse, Fred; Schouten, Jan S

    2012-02-01

    To evaluate the long-term effects and costs of four treatment strategies for primary open-angle glaucoma compared to usual care. Cost-effectiveness analyses with a lifelong horizon were made from a societal perspective. Data were generated with a patient-level model based on discrete event simulation. The model structure and parameter estimates were based on literature, particularly clinical studies on the natural course of glaucoma and the effect of treatment. We simulated heterogeneous cohorts of 3000 patients and explored the impact of uncertainty with sensitivity analyses. The incremental cost-effectiveness ratio (ICER) of initial treatment with a prostaglandin analogue compared with a β-blocker was €12.931 per quality-adjusted life year (QALY) gained. A low initial target pressure (15 mmHg) resulted in 0.115 QALYs gained and €1550 saved compared to a gradual decrease from 21 to 15 mmHg upon progression. Visual field (VF) measurements every 6 rather than 12 months lead to health gains at increased costs (ICER €173,486 per QALY gained), whereas measurements every 24 months lead to health losses at reduced costs (ICER €21,516 per QALY lost). All treatment strategies were dominant over 'withholding treatment'. From a cost-effectiveness point of view, it seems advantageous to aim for a low intraocular pressure in all glaucoma patients. The feasibility of this strategy should therefore be investigated. Additionally, the cost-effectiveness outcomes of initiating monotherapy with a prostaglandin analogue and reducing the frequency of VF testing may be acceptable. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

  7. [Macular choroidal blood flow in concurrent age-related macular degeneration and primary open-angle glaucoma].

    PubMed

    Panova, I E; Ermak, E M; Shaimova, T A; Shaimova, V A

    2016-01-01

    Ocular circulation disorders are an important factor in the development of primary open-angle glaucoma (POAG) and age-related macular degeneration (AMD). To date, however, there have been no studies on choroidal blood flow peculiarities in case of concurrent AMD and POAG. to determine distinctive features of choroidal blood flow characteristic of concurrent AMD and POAG and to assess their role in disease pathogenesis. Macular choroidal blood flow, including blood supply, was assessed in 54 patients (102 eyes) by means of Doppler ultrasound. Three groups were formed: group 1 - 38 eyes with both AMD and POAG; group 2 - 41 eyes with AMD and no signs of optic nerve pathology; and group 3 - 23 eyes with POAG and no signs of AMD. Groups 1 and 2 were subdivided into two subgroups each: А - atrophic AMD and B - macular drusen. The mean patient age was 78.7±8.4 years. The following parameters of choroidal blood flow were of interest: peak systolic velocity (Vps), end diastolic velocity (Ved), time-averaged maximum velocity (Vtamax), and resistance index (RI). Groups 1, 3, and 2A had an evident choroidal hypoperfusion in the macular area (decreased Vtamax) with uncompensated perfusion deficit, despite autoregulation efforts (decreased Vps, Ved, decreased or normal RI). Group 2B demonstrated a significantly higher rate of choroidal hyperperfusion (increased Vps, Ved, Vtamax, and RI). Concurrent AMD and POAG are notable for choroidal hypoperfusion in the macular area that leads to inadequate trophism of the neurosensory retina and can aggravate the course of AMD contributing to progression of its atrophic form.

  8. Dependence of diameters and oxygen saturation of retinal vessels on visual field damage and age in primary open-angle glaucoma.

    PubMed

    Ramm, Lisa; Jentsch, Susanne; Peters, Sven; Sauer, Lydia; Augsten, Regine; Hammer, Martin

    2016-05-01

    To investigate the interrelationship between the oxygen supply of the retina and its regulation with the severity of primary open-angle glaucoma (POAG). Central retinal artery (CRAE) and vein (CRVE) diameters and oxygen saturation of peripapillary retinal vessels in 41 patients suffering from POAG (64.1 ± 12.9 years) and 40 healthy volunteers (63.6 ± 14.1 years) were measured using the retinal vessel analyzer. All measures were taken before and during flicker light stimulation. The mean retinal nerve fiber layer thickness (RNFLT) was determined by OCT and the visual field mean defect (MD) was identified using perimetry. In glaucoma patients, CRAE (r = -0.48 p = 0.002) and CRVE (r = -0.394 p = 0.014) at baseline were inversely related to MD, while arterial and venous oxygen saturation showed no significant dependence on the severity of the damage. However, the flicker light-induced change in arterio-venous difference in oxygen saturation was correlated with the MD (r = 0.358 p = 0.027). The diameters of arteries and veins at baseline decreased with reduction of the mean RNFLT (arteries: r = 0.718 p < 0.001; veins: r = 0.685 p < 0.001). Vessel diameters showed a strong correlation with RNFLT and MD. This, as well as the reduction of stimulation-induced change in arterio-venous oxygen saturation difference with visual field loss, may be explained by a reduction of the retinal metabolic demand with progressive loss of neuronal tissue in glaucoma. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  9. Changes in the retrobulbar arterial circulation after decrease of elevated intraocular pressue in patients with primary open angle glaucoma.

    PubMed

    Marjanović, Ivan; Sundić, Ana; Mijajlović, Milija; Covicković-Sternić, Nadezda; Kontić, Djordje; Hentova-Senćanić, Paraskeva; Marković, Vujica; Bozić, Marija; Knezević, Miroslav

    2011-01-01

    An altered perfusion of the optic nerve head has been proposed as a pathogenic factor in glaucoma. To evaluate changes of haemodynamic parameters in the retrobulbar arterial circulation after a decrease of elevated intraocular pressure (IOP) in patients with primary open angle glaucoma (POAG). Twenty-six patients were examined, 14 men and 12 women, 21 up to 50 years old and 5 below, all with previously diagnosed and treated POAG, and all examined at the Eye Clinic, Clinical Centre of Serbia. IOP was measured both with a Goldmann aplanation tonometer and dynamic contour tonometer. Central corneal thickness was measured with ultrasound pachymeter. Imaging of the retrobulbar arterial circulation by colour Doppler was performed at the Neurology Clinic, Clinical Centre of Serbia. It involved measuring of haemodynamic parameters of the ophthalmic artery, central retinal artery, and posterior ciliary arteries. Peak systolic velocity (PSV) and end-diastolic velocity (EDV) were measured, and resistive index (RI) and pulsatility index (PI) were calculated. Haemodynamic arterial parameters PSV and EDV in the ophthalmic and central retinal artery after decrease of IOP were lower, while RI and PI were higher. In the posterior ciliary arteries PSV, EDV and PI were lower, and RI was higher. Changes of the retrobulbar arterial circulation after elevated LOP in POAG patients are important for approach and treatment, while the role of vascular factors in the supplement of the optic disc neuroretinal rim could be a key for progression backlash of glaucoma and the radix of neuroprotection.

  10. Refractory open-angle glaucoma after neodymium-yttrium-aluminum-garnet laser lysis of vitreous floaters.

    PubMed

    Cowan, Lisa A; Khine, Kay T; Chopra, Vikas; Fazio, Doreen T; Francis, Brian A

    2015-01-01

    To illustrate 3 cases of chronic open-angle glaucoma secondary to the neodymium-yttrium-aluminum-garnet (Nd:YAG) laser vitreolysis procedure for symptomatic vitreous floaters. Observational case series. Location of the study was the Doheny Eye Institute. Three eyes of 2 patients who developed chronic open-angle glaucoma after Nd:YAG vitreolysis for symptomatic floaters presenting with very high intraocular pressure (IOP >40 mm Hg) were selected. The time from the laser treatment to the onset of elevated pressure ranges from 1 week to 8 months. There was no associated inflammation, steroid use, or other identifiable cause of chronic IOP elevation. All eyes were treated initially with glaucoma medication, followed by selective laser trabeculoplasty (SLT) and eventually glaucoma surgery (Trabectome) in 2 eyes for disease management. In all eyes, intraocular pressures were eventually stabilized within a normal pressure range from 18 to 38 months following Nd:YAG vitreolysis. At the latest follow-up post surgery, all eyes had intraocular pressures of 22 mm Hg or less with or without medications. Secondary open-angle glaucoma is a complication of Nd:YAG vitreolysis for symptomatic floaters that may present with an increase in intraocular pressure immediately, or many months after the surgery. Furthermore this complication may be permanent and require chronic medical therapy or glaucoma surgery. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. A target field design of open multi-purpose RF coil for musculoskeletal MR imaging at 3T.

    PubMed

    Gao, Fei; Zhang, Rui; Zhou, Diange; Wang, Xiaoying; Huang, Kefu; Zhang, Jue

    2016-10-01

    Musculoskeletal MR imaging under multi-angle situations plays an increasingly important role in assessing joint and muscle tissues system. However, there are still limitations due to the closed structures of most conventional RF coils. In this study, a time-harmonic target-field method was employed to design open multi-purpose coil (OMC) for multi-angle musculoskeletal MR imaging. The phantom imaging results suggested that the proposed OMC could achieve homogeneously distributed magnetic field and high signal-to-noise ratio (SNR) of 239.04±0.83 in the region of interest (ROI). The maximum temperature in the heating hazard test was 16°C lower than the standard regulation, which indicated the security of the designed OMC. Furthermore, to demonstrate the effectiveness of the proposed OMC for musculoskeletal MR imaging, especially for multi-angle imaging, a healthy volunteer was examined for MR imaging of elbow, ankle and knee using OMC. The in vivo imaging results showed that the proposed OMC is effective for MR imaging of musculoskeletal tissues at different body parts, with satisfied B1 field homogeneity and SNR. Moreover, the open structure of the OMC could provide a large joint movement region. The proposed open multi-purpose coil is feasible for musculoskeletal MR imaging, and potentially, it is more suitable for the evaluation of musculoskeletal tissues under multi-angle conditions. Copyright © 2016. Published by Elsevier Inc.

  12. LOXL1 deficiency in the lamina cribrosa as candidate susceptibility factor for a pseudoexfoliation-specific risk of glaucoma.

    PubMed

    Schlötzer-Schrehardt, Ursula; Hammer, Christian M; Krysta, Anita W; Hofmann-Rummelt, Carmen; Pasutto, Francesca; Sasaki, Takako; Kruse, Friedrich E; Zenkel, Matthias

    2012-09-01

    To test the hypothesis that a primary disturbance in lysyl oxidase-like 1 (LOXL1) and elastin metabolism in the lamina cribrosa of eyes with pseudoexfoliation syndrome constitutes an independent risk factor for glaucoma development and progression. Observational, consecutive case series. Posterior segment tissues obtained from 37 donors with early and late stages of pseudoexfoliation syndrome without glaucoma, 37 normal age-matched control subjects, 5 eyes with pseudoexfoliation-associated open-angle glaucoma, and 5 eyes with primary open-angle glaucoma (POAG). Protein and mRNA expression of major elastic fiber components (elastin, fibrillin-1, fibulin-4), collagens (types I, III, and IV), and lysyl oxidase crosslinking enzymes (LOX, LOXL1, LOXL2) were assessed in situ by quantitative real-time polymerase chain reaction, (immuno)histochemistry, and light and electron microscopy. Lysyl oxidase-dependent elastin fiber assembly was assessed by primary optic nerve head astrocytes in vitro. Expression levels of elastic proteins, collagens, and lysyl oxidases in the lamina cribrosa. Lysyl oxidase-like 1 proved to be the major lysyl oxidase isoform in the normal lamina cribrosa in association with a complex elastic fiber network. Compared with normal and POAG specimens, lamina cribrosa tissues obtained from early and late stages of pseudoexfoliation syndrome without and with glaucoma consistently revealed a significant coordinated downregulation of LOXL1 and elastic fiber constituents on mRNA and protein level. In contrast, expression levels of collagens and other lysyl oxidase isoforms were not affected. Dysregulated expression of LOXL1 and elastic proteins was associated with pronounced (ultra)structural alterations of the elastic fiber network in the laminar beams of pseudoexfoliation syndrome eyes. Inhibition of LOXL1 interfered with elastic fiber assembly by optic nerve head astrocytes in vitro. The findings provide evidence for a pseudoexfoliation-specific elastinopathy of the lamina cribrosa resulting from a primary disturbance in LOXL1 regulation and elastic fiber homeostasis, possibly rendering pseudoexfoliation syndrome eyes more vulnerable to pressure-induced optic nerve damage and glaucoma development and progression. Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  13. Demonstration of angle widening using EyeCam after laser peripheral iridotomy in eyes with angle closure.

    PubMed

    Perera, Shamira A; Quek, Desmond T; Baskaran, Mani; Tun, Tin A; Kumar, Rajesh S; Friedman, David S; Aung, Tin

    2010-06-01

    To evaluate EyeCam in detecting changes in angle configuration after laser peripheral iridotomy (LPI) in comparison to gonioscopy, the reference standard. Prospective comparative study. Twenty-four subjects (24 eyes) with primary angle-closure glaucoma (PACG) were recruited. Gonioscopy and EyeCam (Clarity Medical Systems) imaging of all 4 angle quadrants were performed, before and 2 weeks after LPI. Images were graded according to angle structures visible by an observer masked to clinical data or the status of LPI, and were performed in a random order. Angle closure in a quadrant was defined as the inability to visualize the posterior trabecular meshwork. We determined the number of quadrants with closed angles and the mean number of clock hours of angle closure before and after LPI in comparison to gonioscopy. Using EyeCam, all 24 eyes showed at least 1 quadrant of angle widening after LPI. The mean number of clock hours of angle closure decreased significantly, from 8.15 +/- 3.47 clock hours before LPI to 1.75 +/- 2.27 clock hours after LPI (P < .0001, Wilcoxon signed rank test). Overall, gonioscopy showed 1.0 +/- 1.41 (95% CI, 0.43-1.57) quadrants opening from closed to open after LPI compared to 2.0 +/- 1.28 (95% CI, 1.49-2.51, P = .009) quadrants with EyeCam. Intra-observer reproducibility of grading the extent of angle closure in clock hours in EyeCam images was moderate to good (intraclass correlation coefficient 0.831). EyeCam may be used to document changes in angle configuration after LPI in eyes with PACG. Copyright 2010 Elsevier Inc. All rights reserved.

  14. Representation of the equatorial stratospheric quasi-biennial oscillation in EOF phase space. [EOF (empirical orthogonal function)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wallace, J.M.; Panetta, R.L.; Estberg, J.

    1993-06-15

    A 35-year record of monthly mean zonal wind data for the equatorial stratosphere is represented in terms of a vector (radius and phase angle) in a two-dimensional phase space defined by the normalized expansion coefficients of the two leading empirical orthogonal functions (EOFs) of the vertical structure. The tip of the vector completes one nearly circular loop during each cycle of the quasi-biennial oscillation (QBO). Hence, its position and rate of progress along the orbit of the point provide a measure of the instantaneous amplitude and rate of phase progression of the QBO. Although the phase of the QBO bearsmore » little if any relation to calendar month, the rate of phase progression is strongly modulated by the first and second harmonics of the annual cycle, with a primary maximum in April/May, in agreement with previous studies based on the descent rates of easterly and westerly regimes. A simple linear prediction model is developed for the rate of phase progression, based on the phase of the QBO and the phase of the annual cycle. The model is capable of hindcasting the phase of the QBO to within a specified degree of accuracy approximately 50% longer than a default scheme based on the mean observed rate of phase progression of the QBO (1 cycle per 28.1 months). If the seasonal dependence is ignored, the prediction equation corresponds to the [open quotes]circle map,[close quotes] for which an extensive literature exists in dynamical systems theory. 17 refs., 14 figs., 2 tabs.« less

  15. Dental and skeletal components of Class II open bite treatment with a modified Thurow appliance

    PubMed Central

    Jacob, Helder Baldi; dos Santos-Pinto, Ary; Buschang, Peter H.

    2014-01-01

    Introduction Due to the lack of studies that distinguish between dentoalveolar and basal changes caused by the Thurow appliance, this clinical study, carried out by the School of Dentistry - State University of São Paulo/Araraquara, aimed at assessing the dental and skeletal changes induced by modified Thurow appliance. Methods The sample included an experimental group comprising 13 subjects aged between 7 and 10 years old, with Class II malocclusion and anterior open bite, and a control group comprising 22 subjects similar in age, sex and mandibular plane angle. Maxillary/mandibular, horizontal/vertical, dental/skeletal movements (ANS, PNS, U1, U6, Co, Go, Pog, L1, L6) were assessed, based on 14 landmarks, 8 angles (S-N-ANS, SNA, PPA, S-N-Pog, SNB, MPA, PP/MPA, ANB) and 3 linear measures (N-Me, ANS-Me, S-Go). Results Treatment caused significantly greater angle decrease between the palatal and the mandibular plane of the experimental group, primarily due to an increase in the palatal plane angle. ANB, SNA and S-N-ANS angles significantly decreased more in patients from the experimental group. PNS was superiorly remodeled. Lower face height (ANS-Me) decreased in the experimental group and increased in the control group. Conclusions The modified Thurow appliance controlled vertical and horizontal displacements of the maxilla, rotated the maxilla and improved open bite malocclusion, decreasing lower facial height. PMID:24713556

  16. Progress in anterior chamber angle imaging for glaucoma risk prediction - A review on clinical equipment, practice and research.

    PubMed

    V K, Shinoj; Hong, Xun Jie Jeesmond; V M, Murukeshan; M, Baskaran; Tin, Aung

    2016-12-01

    The visualization capabilities of various ocular imaging instruments can generally be categorized into photographic (e.g. gonioscopy, Pentacam, RetCam) and optical tomographic (e.g. optical coherence tomography (OCT), photoacoustic (PA) imaging, ultrasound biomicriscopy (UBM)) methods. These imaging instruments allow vision researchers and clinicians to visualize the iridocorneal angle, and are essential in the diagnosis and management of glaucoma. Each of these imaging modalities has particular benefits and associated drawbacks in obtaining repeatable and reliable measurement in the evaluation of the angle. This review article in this context summarized recent progresses in anterior chamber imaging techniques in glaucoma diagnosis and follow-up procedures. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

  17. Open-ocean fish reveal an omnidirectional solution to camouflage in polarized environments.

    PubMed

    Brady, Parrish C; Gilerson, Alexander A; Kattawar, George W; Sullivan, James M; Twardowski, Michael S; Dierssen, Heidi M; Gao, Meng; Travis, Kort; Etheredge, Robert Ian; Tonizzo, Alberto; Ibrahim, Amir; Carrizo, Carlos; Gu, Yalong; Russell, Brandon J; Mislinski, Kathryn; Zhao, Shulei; Cummings, Molly E

    2015-11-20

    Despite appearing featureless to our eyes, the open ocean is a highly variable environment for polarization-sensitive viewers. Dynamic visual backgrounds coupled with predator encounters from all possible directions make this habitat one of the most challenging for camouflage. We tested open-ocean crypsis in nature by collecting more than 1500 videopolarimetry measurements from live fish from distinct habitats under a variety of viewing conditions. Open-ocean fish species exhibited camouflage that was superior to that of both nearshore fish and mirrorlike surfaces, with significantly higher crypsis at angles associated with predator detection and pursuit. Histological measurements revealed that specific arrangements of reflective guanine platelets in the fish's skin produce angle-dependent polarization modifications for polarocrypsis in the open ocean, suggesting a mechanism for natural selection to shape reflectance properties in this complex environment. Copyright © 2015, American Association for the Advancement of Science.

  18. Filtering data from the collaborative initial glaucoma treatment study for improved identification of glaucoma progression.

    PubMed

    Schell, Greggory J; Lavieri, Mariel S; Stein, Joshua D; Musch, David C

    2013-12-21

    Open-angle glaucoma (OAG) is a prevalent, degenerate ocular disease which can lead to blindness without proper clinical management. The tests used to assess disease progression are susceptible to process and measurement noise. The aim of this study was to develop a methodology which accounts for the inherent noise in the data and improve significant disease progression identification. Longitudinal observations from the Collaborative Initial Glaucoma Treatment Study (CIGTS) were used to parameterize and validate a Kalman filter model and logistic regression function. The Kalman filter estimates the true value of biomarkers associated with OAG and forecasts future values of these variables. We develop two logistic regression models via generalized estimating equations (GEE) for calculating the probability of experiencing significant OAG progression: one model based on the raw measurements from CIGTS and another model based on the Kalman filter estimates of the CIGTS data. Receiver operating characteristic (ROC) curves and associated area under the ROC curve (AUC) estimates are calculated using cross-fold validation. The logistic regression model developed using Kalman filter estimates as data input achieves higher sensitivity and specificity than the model developed using raw measurements. The mean AUC for the Kalman filter-based model is 0.961 while the mean AUC for the raw measurements model is 0.889. Hence, using the probability function generated via Kalman filter estimates and GEE for logistic regression, we are able to more accurately classify patients and instances as experiencing significant OAG progression. A Kalman filter approach for estimating the true value of OAG biomarkers resulted in data input which improved the accuracy of a logistic regression classification model compared to a model using raw measurements as input. This methodology accounts for process and measurement noise to enable improved discrimination between progression and nonprogression in chronic diseases.

  19. The Properties of Extragalactic Radio Jets

    NASA Astrophysics Data System (ADS)

    Finke, Justin

    2018-01-01

    I show that by assuming a standard Blandford-Konigl jet, it is possible to determine the speed (bulk Lorentz factor) and orientation (angle to the line of sight) of self-similar parsec-scale blazar jets by using four measured quantities: the core radio flux, the extended radio flux, the magnitude of the core shift between two frequencies, and the apparent jet opening angle. Once the bulk Lorentz factor and angle to the line of sight of a jet are known, it is possible to compute their Doppler factor, magnetic field, and intrinsic jet opening angle. I use data taken from the literature and marginalize over nuisance parameters associated with the electron distribution and equipartition, to compute these quantities, albeit with large errors. The results have implications for the resolution of the TeV BL Lac Doppler factor crisis and the production of jets from magnetically arrested disks.

  20. A comparison of latanoprost monotherapy with a combination therapy of timolol/dorzolamide in patients with primary open-angle glaucoma.

    PubMed

    Caça, Ihsan; Simsek, Hüseyin; Unlü, Kaan; Ari, Seyhmus; Keklikçi, Ugur

    2006-01-01

    We compared latanoprost monotherapy therapy with timolol/ dorzolamide in patients with primary open-angle glaucoma to evaluate the effects on intraocular pressure (IOP) and occurrence of adverse events. IOP and topical side effects were evaluated at the beginning, first, and third months. Mean IOP was decreased at the third month. The most common side effect was hyperemia (43.6%). We concluded that latanoprost reduces IOP better than fixed combination and its topical side effects are tolerable.

  1. Conservative treatment of idiopathic scoliosis according to FITS concept: presentation of the method and preliminary, short term radiological and clinical results based on SOSORT and SRS criteria

    PubMed Central

    2011-01-01

    Background Conservative scoliosis therapy according to the FITS Concept is applied as a unique treatment or in combination with corrective bracing. The aim of the study was to present author's method of diagnosis and therapy for idiopathic scoliosis FITS-Functional Individual Therapy of Scoliosis and to analyze the early results of FITS therapy in a series of consecutive patients. Methods The analysis comprised separately: (1) single structural thoracic, thoracolumbar or lumbar curves and (2) double structural scoliosis-thoracic and thoracolumbar or lumbar curves. The Cobb angle and Risser sign were analyzed at the initial stage and at the 2.8-year follow-up. The percentage of patients improved (defined as decrease of Cobb angle of more than 5 degrees), stable (+/- 5 degrees), and progressed (increase of Cobb angle of more than 5 degrees) was calculated. The clinical assessment comprised: the Angle of Trunk Rotation (ATR) initial and follow-up value, the plumb line imbalance, the scapulae level and the distance from the apical spinous process of the primary curve to the plumb line. Results In the Group A: (1) in single structural scoliosis 50,0% of patients improved, 46,2% were stable and 3,8% progressed, while (2) in double scoliosis 50,0% of patients improved, 30,8% were stable and 19,2% progressed. In the Group B: (1) in single scoliosis 20,0% of patients improved, 80,0% were stable, no patient progressed, while (2) in double scoliosis 28,1% of patients improved, 46,9% were stable and 25,0% progressed. Conclusion Best results were obtained in 10-25 degrees scoliosis which is a good indication to start therapy before more structural changes within the spine establish. PMID:22122964

  2. Patterns of folding and fold interference in oblique contraction of layered rocks of the inverted Cobar Basin, Australia

    NASA Astrophysics Data System (ADS)

    Smith, J. V.; Marshall, B.

    1992-12-01

    The inverted Cobar Basin, within the Lachlan Fold Belt of New South Wales, Australia, comprises a mid-Palaeozoic cover sequence, originally deposited in a NNW-trending basin. The pattern of F 1 folding in the layered cover rocks changes from east to west; from tight well-cleaved folds parallel to the NNW-trending basin margin on the east, to open poorly cleaved en echelon folds at about 35° to the margin, further to the west. The change in fold trend and strain intensity has been repeatedly ascribed to the differing behaviour of discrete zones, decoupled across a north-trending strike-slip fault boundary. New field data show that the changes in orientation and strain intensity of F 1 structures are progressively developed, that an abrupt boundary between discrete zones cannot be substantiated, and that interpretations involving decoupled blocks are not supported by the evidence. Conversely, the data require coherent behaviour across the basin, such that the overall pattern of F 1 folding must be explained by strain compatible processes. This new interpretation of the F 1 deformation pattern has been modelled and quantitatively analysed. Theoretical predictions of the orientation of structures in unlayered isotropic material undergoing oblique contraction are inapplicable to layered anisotropic material. The style of deformation in layered material will reflect the interaction of the bulk strain pattern due to convergence together with the influence of the layering anisotropy. The orientations of the finite strain axes inferred from the folding need not match those of the bulk deformation; the amount of strain recorded by folding may be unrepresentative of that developed in the deformed tract. Oblique contraction at a range of convergence angles was simulated by models employing layers of wet tissue paper. Quantitative analysis of the strain patterns in this layered anisotropic material showed consistent departures from the theoretical predictions for isotropic material. The orientations of the principal finite horizontal extension proximal to the margin yielded higher convergence angles than those which were imposed; the orientations distal from the margin yielded substantially lower apparent convergence angles. This is because the layering anisotropy results in tight folds dissipating the normal component of the oblique convergence vector close to the margin. Whereas more open structures further from the margin show orientations controlled by the progressively more dominant shear component of the vergence vector. Modelling of D 1 the Cobar Basin shows that the F 1 pattern is consistent with dextral oblique convergence at 60° to the eastern margin of the basin. The deformation patterns, in both the model and the Cobar Basin, yield higher proximal and substantially lower distal apparent convergence angles. This is as expected from theoretical considerations and quantitative analysis of oblique contraction over a range of convergence angles. The rheological anisotropy of the cover sequence of the basin is replicated by that of the layered wet tissue paper. Wet-tissue modelling of the superposition of the second period of deformation (D 2) on F 1 demonstrates the way in which the tightness and orientation of early folds influence the type of fold interference pattern. At the eastern margin of the Cobar Basin, where D 1 was most intense, this resulted in major swings of the strike of bedding and cleavage, and of the trend of F 1 folds. Further west, open basin and dome patterns developed where D 1 was least intense. Principles developed in relation to the inversion of the Cobar Basin, are equally applicable to other basins in which layered cover rocks have undergone inversion by oblique contraction. Many basins in the Lachlan Fold Belt and in general would fall within this category.

  3. Static balance according to hip joint angle of unsupported leg during one-leg standing.

    PubMed

    Cha, Ju-Hyung; Kim, Jang-Joon; Ye, Jae-Gwan; Lee, Seul-Ji; Hong, Jeong-Mi; Choi, Hyun-Kyu; Choi, Ho-Suk; Shin, Won-Seob

    2017-05-01

    [Purpose] This study aimed to determine static balance according to hip joint angle of the unsupported leg during one-leg standing. [Subjects and Methods] Subjects included 45 healthy adult males and females in their 20s. During one-leg standing on the non-dominant leg, the position of the unsupported leg was classified according to hip joint angles of point angle was class. Static balance was then measured using a force plate with eyes open and closed. The total length, sway velocity, maximum deviation, and velocity on the mediolateral and anteroposterior axes of center of pressure were measured. [Results] In balance assessment with eyes open, there were significant differences between groups according to hip joint angle, except for maximum deviation on the anteroposterior axis. In balance assessment with eyes closed, there were significant differences between total length measurements at 0° and 30°, 60° and between 30° and 90°. There were significant differences between sway velocity measurements at 0° and 30° and between 30° and 90°. [Conclusion] Thus, there were differences in static balance according to hip joint angle. It is necessary to clearly identify the hip joint angle during one-leg standing testing.

  4. Detection of progressive idiopathic scoliosis during growth using back surface topography: a prospective study of 100 patients.

    PubMed

    De Korvin, G; Randriaminahisoa, T; Cugy, E; Cheze, L; de Sèze, M

    2014-12-01

    The progression of adolescent idiopathic scoliosis is typically monitored via regular radiographic follow-up. The Cobb angle (as measured on whole-spine radiographs) is considered as the gold standard in scoliosis monitoring. To determine the sensitivity and specificity of back surface topography parameters, with a view to detecting changes in the Cobb angle. One hundred patients (mean age: 13.3) with Cobb angles greater than 10 degrees were included. Topographic parameters were measured in a standard position and in a position with hunched shoulders. Gibbosities and spinal curvatures were evaluated. An increase of more than 2 degrees in any one gibbosity or in the sum of the gibbosities (in either of the two examination positions) enabled the detection of a five-degree increase in the Cobb angle with a sensitivity of 86% and a specificity of 50%. If the present results are confirmed by other studies, analysis with back surface topography parameters may reduce the number of X-ray examinations required to detect increases in the Cobb angle. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  5. Patterns of Progressive Ganglion Cell-Inner Plexiform Layer Thinning in Glaucoma Detected by OCT.

    PubMed

    Shin, Joong Won; Sung, Kyung Rim; Park, Sun-Won

    2018-04-25

    To investigate the spatial characteristics and patterns of progressive macular ganglion cell-inner plexiform layer (GCIPL) thinning in glaucomatous eyes assessed by OCT Guided Progression Analysis (GPA). Longitudinal, retrospective, observational study. Two hundred ninety-two eyes of 192 patients with primary open-angle glaucoma with a mean follow-up of 6.0 years (range, 3.2-8.1 years) were included. Macular GCIPL imaging and visual field (VF) examination were performed at 6-month intervals for 3 years or more. Progressive GCIPL thinning was evaluated by a Cirrus HD-OCT (Carl Zeiss Meditec, Dublin, CA) GPA device. Spatial characteristics of progressive GCIPL thinning were assessed by the GCIPL thickness change map. The pattern of progressive GCIPL thinning was evaluated by comparing the baseline GCIPL thickness deviation map and the final GCIPL thickness change map. Visual field progression was determined by Early Manifest Glaucoma Trial criteria and linear regression of the VF index. Spatial characteristics and patterns of progressive GCIPL thinning. Seventy-two eyes of 62 participants (24.7% [72/292]) showed progressive GCIPL thinning in the GCIPL thickness change map. Progressive GCIPL thinning was detected most frequently (25.0%) at 2.08 mm from the fovea, and it extended in an arcuate shape in the inferotemporal region (250°-339°). Compared with the baseline GCIPL defects, the progressive GCIPL thinning extended toward the fovea and optic disc. The most common pattern of progressive GCIPL thinning was widening of GCIPL defects (42 eyes [58.3%]), followed by deepening of GCIPL defects (19 eyes [26.4%]) and newly developed GCIPL defects (15 eyes [20.8%]). Visual field progression was accompanied by progressive GCIPL thinning in 41 of 72 eyes (56.9%). Progressive GCIPL thinning preceded (61.0% [25/41]) or occurred concomitantly with (21.9% [9/41]) VF progression. The use of OCT GPA maps offers an effective approach to evaluate the topographic patterns of progressive GCIPL thinning in glaucomatous eyes. Progression of GCIPL thinning occurred before apparent progression on standard automated perimetry in most glaucomatous eyes. Understanding specific patterns and sequences of macular damage may provide important insights in the monitoring of glaucomatous progression. Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  6. An innovative small angle slot divertor concept for long pulse advanced tokamaks

    NASA Astrophysics Data System (ADS)

    Guo, Houyang

    2017-10-01

    A new Small Angle Slot (SAS) divertor is being developed in DIII-D to address the challenge of efficient divertor heat dispersal at the relatively low plasma density required for non-inductive current drive in future advanced tokamaks. SAS features a small incident angle near the plasma strike point on the divertor target plate with a progressively opening slot. SOLPS (B2-Eirene) edge code analysis finds that SAS can achieve strong plasma cooling when the strike point is placed near the small angle target plate in the slot, leading to low electron temperature Te across the entire divertor target. This is enabled by strong coupling between a gas tight slot and directed neutral recycling by the small angle target to enhance neutral buildup near the target. SOLPS analysis reveals a strong correlation between Te and D2 density at the target for various divertor configurations including the flat target, slanted target, and lower single null divertor. The strong correlation suggests that achievement of low Te may reduce essentially to identifying the divertor baffle geometry that achieves the highest target gas density at a given upstream condition. The SAS divertor concept has recently been tested in DIII-D for a range of plasma configurations and conditions with precise control of slot strike point location. In confirmation of SOLPS predictions, a sharp transition is observed when the strike point is moved to the critical outer corner of SAS. A set of Langmuir probes imbedded in SAS show that the Te radial profile, which is peaked at the strike point when it is located away from the SAS corner, becomes low across the target when the strike point is located near the corner. With further increase in density, deep-slot detachment occurs with Te 1 eV, measured by the unique DIII-D divertor Thomson Scattering diagnostic. Work supported by US DOE under DE-FC02-04ER54698.

  7. Quasiparticle self-consistent GW study of cuprates: electronic structure, model parameters, and the two-band theory for Tc.

    PubMed

    Jang, Seung Woo; Kotani, Takao; Kino, Hiori; Kuroki, Kazuhiko; Han, Myung Joon

    2015-07-24

    Despite decades of progress, an understanding of unconventional superconductivity still remains elusive. An important open question is about the material dependence of the superconducting properties. Using the quasiparticle self-consistent GW method, we re-examine the electronic structure of copper oxide high-Tc materials. We show that QSGW captures several important features, distinctive from the conventional LDA results. The energy level splitting between d(x(2)-y(2)) and d(3z(2)-r(2)) is significantly enlarged and the van Hove singularity point is lowered. The calculated results compare better than LDA with recent experimental results from resonant inelastic xray scattering and angle resolved photoemission experiments. This agreement with the experiments supports the previously suggested two-band theory for the material dependence of the superconducting transition temperature, Tc.

  8. Comparative assessment of bone pose estimation using Point Cluster Technique and OpenSim.

    PubMed

    Lathrop, Rebecca L; Chaudhari, Ajit M W; Siston, Robert A

    2011-11-01

    Estimating the position of the bones from optical motion capture data is a challenge associated with human movement analysis. Bone pose estimation techniques such as the Point Cluster Technique (PCT) and simulations of movement through software packages such as OpenSim are used to minimize soft tissue artifact and estimate skeletal position; however, using different methods for analysis may produce differing kinematic results which could lead to differences in clinical interpretation such as a misclassification of normal or pathological gait. This study evaluated the differences present in knee joint kinematics as a result of calculating joint angles using various techniques. We calculated knee joint kinematics from experimental gait data using the standard PCT, the least squares approach in OpenSim applied to experimental marker data, and the least squares approach in OpenSim applied to the results of the PCT algorithm. Maximum and resultant RMS differences in knee angles were calculated between all techniques. We observed differences in flexion/extension, varus/valgus, and internal/external rotation angles between all approaches. The largest differences were between the PCT results and all results calculated using OpenSim. The RMS differences averaged nearly 5° for flexion/extension angles with maximum differences exceeding 15°. Average RMS differences were relatively small (< 1.08°) between results calculated within OpenSim, suggesting that the choice of marker weighting is not critical to the results of the least squares inverse kinematics calculations. The largest difference between techniques appeared to be a constant offset between the PCT and all OpenSim results, which may be due to differences in the definition of anatomical reference frames, scaling of musculoskeletal models, and/or placement of virtual markers within OpenSim. Different methods for data analysis can produce largely different kinematic results, which could lead to the misclassification of normal or pathological gait. Improved techniques to allow non-uniform scaling of generic models to more accurately reflect subject-specific bone geometries and anatomical reference frames may reduce differences between bone pose estimation techniques and allow for comparison across gait analysis platforms.

  9. Linkage analysis excludes the glaucoma locus on 1q from involvement in autosomal dominant glaucoma with iris hypoplasia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Heon, E.; Sheth, B.P.; Kalenak, J.W.

    1994-09-01

    Genetic factors have been implicated in a variety of types of glaucoma including primary open-angle glaucoma, infantile glaucoma, pigmentary glaucoma, and juvenile open-angle glaucoma. We previously mapped the disease-causing gene for one type of juvenile open angle glaucoma to chromosome 1q21-31. Weatherill and Hart (1969) and Pearce (1983) each noted the association of iris hypoplasia and early-onset autosomal dominant glaucoma. We recently had the opportunity to study a large family (12 affected members) with this phenotype. Affected individuals developed glaucoma at an average age of 30 years. These patients also have a strikingly underdeveloped iris stroma which causes a peculiarmore » eye color. Linkage analysis was able to completely exclude the 1q glaucoma locus from involvement in the disorder that affects this family. A complete clinical description of the family and linkage results at additional candidate loci will be presented.« less

  10. iStent trabecular micro-bypass stent for open-angle glaucoma

    PubMed Central

    Le, Kim; Saheb, Hady

    2014-01-01

    Trabecular micro-bypass stents, commonly known as iStents, are micro-invasive glaucoma surgery (MIGS) devices used to treat open-angle glaucoma. Like other MIGS procedures that enhance trabecular outflow, the iStent lowers intraocular pressure (IOP) by creating a direct channel between the anterior chamber and Schlemm’s canal. iStents are typically implanted at the time of phacoemulsification for patients with open-angle glaucoma and visually significant cataracts. This review summarizes the published data regarding the efficacy, safety, and cost considerations of trabecular micro-bypass stents. Most studies found statistically significant reductions in mean IOP and ocular medication use after combined phacoemulsification with single or double iStent implantation. The devices were found to be very safe, with a safety profile similar to that of cataract surgery. Complications were infrequent, with the most common complications being temporary stent obstruction or malposition, which resolved with observation or secondary procedures. Future studies are needed to evaluate long-term outcomes, patient satisfaction, cost effectiveness, and expanded indications. PMID:25284980

  11. Open Data in Biomedical Science: Policy Drivers and Recent Progress

    EPA Science Inventory

    EPA's progress in implementing the open data initiatives first outlined in the 2009 Presidential memorandum on open government and more specifically regarding publications and data from publications in the 2013 Holdren memorandum. The presentation outlines the major points in bo...

  12. Early Clinical Results of a Novel Ab Interno Gel Stent for the Surgical Treatment of Open-angle Glaucoma.

    PubMed

    Sheybani, Arsham; Dick, H Burkhard; Ahmed, Iqbal I K

    2016-07-01

    To evaluate the intraocular pressure (IOP) lowering effect of the XEN140 microfistula gel stent implant for the surgical treatment of open-angle glaucoma. Forty-nine eyes of 49 patients with an IOP>18 mm Hg and ≤35 mm Hg were studied in a prospective nonrandomized multicenter cohort trial of the surgical implantation of the XEN140 implant in patients with open-angle glaucoma. Complete success was defined as a postoperative IOP≤18 mm Hg with ≥20% reduction in IOP at 12 months without any glaucoma medications. Failure was defined as vision loss of light perceptions vision or worse, need for additional glaucoma surgery, or <20% reduction of IOP from baseline. The average age was 64.3 (28.1 to 86.9) years old. Twenty-one eyes had prior failed trabeculectomy with mitomycin C surgery. IOP at 12 months decreased from a mean of 23.1 (±4.1) mm Hg to 14.7 (±3.7) mm Hg for a 36.4% reduction in IOP from baseline. The number of patients at 12 months who achieved an IOP≤18 mm Hg and ≥20% reduction in IOP was 40 (89%). The number of patients who achieved an IOP≤18 mm Hg and ≥20% reduction in IOP without antiglaucoma medications was 18 (40%). The XEN140 gel stent lowers IOP with few complications when implanted for the surgical treatment of open-angle glaucoma.

  13. Juxtacanalicular tissue in pigmentary and primary open angle glaucoma. The hydrodynamic role of pigment and other constituents.

    PubMed

    Murphy, C G; Johnson, M; Alvarado, J A

    1992-12-01

    We tested the hypothesis that obstruction of the juxtacanalicular tissues, by melanin granules in pigmentary glaucoma and by other impermeable material in primary open angle glaucoma, leads to the development of a chronic glaucomatous condition. The distribution and concentration of melanin and other impermeable materials in the juxtacanalicular tissues and elsewhere in the trabecular meshwork was determined in 13 specimens. Six specimens were from patients with pigmentary glaucoma, two from patients with pigment dispersion syndrome, and three from patients with primary open angle glaucoma, as well as two from normal subjects. The effect of these materials on flow resistance was estimated using two hydrodynamic models. In model A, the electron-lucent spaces of the juxtacanalicular tissue were assumed to be open spaces, while in model B, these spaces and spaces filled with ground substance were assumed to be gel filled. In pigmentary glaucoma, 3.5% of the pigment was found in the juxtacanalicular tissue, while 96.5% was found in the corneoscleral and uveoscleral tissues. Permeabilities calculated according to model A were much higher than those expected from estimates of outflow facility in all groups, in agreement with the previous report of Ethier et al. The gel-filled spaces available for fluid flow, as determined by model B, showed no statistically demonstrable differences (pigmentary glaucoma, 32.9%; primary open angle glaucoma, 36.6%; pigment dispersion syndrome, 43.4%; normal, 44.1%). Furthermore, the amount of pigment present in the juxtacanalicular tissue was determined to have a negligible influence on permeability. Thus, the development of the chronic glaucomatous condition cannot be directly attributed to pigment accumulation in the juxtacanalicular tissue in pigmentary glaucoma.

  14. A gait retraining system using augmented-reality to modify footprint parameters: Effects on lower-limb sagittal-plane kinematics.

    PubMed

    Bennour, Sami; Ulrich, Baptiste; Legrand, Thomas; Jolles, Brigitte M; Favre, Julien

    2018-01-03

    Improving lower-limb flexion/extension angles during walking is important for the treatment of numerous pathologies. Currently, these gait retraining procedures are mostly qualitative, often based on visual assessment and oral instructions. This study aimed to propose an alternative method combining motion capture and display of target footprints on the floor. The second objectives were to determine the error in footprint modifications and the effects of footprint modifications on lower-limb flexion/extension angles. An augmented-reality system made of an optoelectronic motion capture device and video projectors displaying target footprints on the floor was designed. 10 young healthy subjects performed a series of 27 trials, consisting of increased and decreased amplitudes in stride length, step width and foot progression angle. 11 standard features were used to describe and compare lower-limb flexion/extension angles among footprint modifications. Subjects became accustomed to walk on target footprints in less than 10 min, with mean (± SD) precision of 0.020 ± 0.002 m in stride length, 0.022 ± 0.006 m in step width, and 2.7 ± 0.6° in progression angle. Modifying stride length had significant effects on 3/3 hip, 2/4 knee and 4/4 ankle features. Similarly, step width and progression angle modifications affected 2/3 and 1/3 hip, 2/4 and 1/4 knee as well as 3/4 and 2/4 ankle features, respectively. In conclusion, this study introduced an augmented-reality method allowing healthy subjects to modify their footprint parameters rapidly and precisely. Walking with modified footprints changed lower-limb sagittal-plane kinematics. Further research is needed to design rehabilitation protocols for specific pathologies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Percutaneous versus traditional and paraspinal posterior open approaches for treatment of thoracolumbar fractures without neurologic deficit: a meta-analysis.

    PubMed

    Sun, Xiang-Yao; Zhang, Xi-Nuo; Hai, Yong

    2017-05-01

    This study evaluated differences in outcome variables between percutaneous, traditional, and paraspinal posterior open approaches for traumatic thoracolumbar fractures without neurologic deficit. A systematic review of PubMed, Cochrane, and Embase was performed. In this meta-analysis, we conducted online searches of PubMed, Cochrane, Embase using the search terms "thoracolumbar fractures", "lumbar fractures", ''percutaneous'', "minimally invasive", ''open", "traditional", "posterior", "conventional", "pedicle screw", "sextant", and "clinical trial". The analysis was performed on individual patient data from all the studies that met the selection criteria. Clinical outcomes were expressed as risk difference for dichotomous outcomes and mean difference for continuous outcomes with 95 % confidence interval. Heterogeneity was assessed using the χ 2 test and I 2 statistics. There were 4 randomized controlled trials and 14 observational articles included in this analysis. Percutaneous approach was associated with better ODI score, less Cobb angle correction, less Cobb angle correction loss, less postoperative VBA correction, and lower infection rate compared with open approach. Percutaneous approach was also associated with shorter operative duration, longer intraoperative fluoroscopy, less postoperative VAS, and postoperative VBH% in comparison with traditional open approach. No significant difference was found in Cobb angle correction, postoperative VBA, VBA correction loss, Postoperative VBH%, VBH correction loss, and pedicle screw misplacement between percutaneous approach and open approach. There was no significant difference in operative duration, intraoperative fluoroscopy, postoperative VAS, and postoperative VBH% between percutaneous approach and paraspianl approach. The functional and the radiological outcome of percutaneous approach would be better than open approach in the long term. Although trans-muscular spatium approach belonged to open fixation methods, it was strictly defined as less invasive approach, which provided less injury to the paraspinal muscles and better reposition effect.

  16. Edge contact angle and modified Kelvin equation for condensation in open pores.

    PubMed

    Malijevský, Alexandr; Parry, Andrew O; Pospíšil, Martin

    2017-08-01

    We consider capillary condensation transitions occurring in open slits of width L and finite height H immersed in a reservoir of vapor. In this case the pressure at which condensation occurs is closer to saturation compared to that occurring in an infinite slit (H=∞) due to the presence of two menisci that are pinned near the open ends. Using macroscopic arguments, we derive a modified Kelvin equation for the pressure p_{cc}(L;H) at which condensation occurs and show that the two menisci are characterized by an edge contact angle θ_{e} that is always larger than the equilibrium contact angle θ, only equal to it in the limit of macroscopic H. For walls that are completely wet (θ=0) the edge contact angle depends only on the aspect ratio of the capillary and is well described by θ_{e}≈sqrt[πL/2H] for large H. Similar results apply for condensation in cylindrical pores of finite length. We test these predictions against numerical results obtained using a microscopic density-functional model where the presence of an edge contact angle characterizing the shape of the menisci is clearly visible from the density profiles. Below the wetting temperature T_{w} we find very good agreement for slit pores of widths of just a few tens of molecular diameters, while above T_{w} the modified Kelvin equation only becomes accurate for much larger systems.

  17. Significance of peak height velocity as a predictive factor for curve progression in patients with idiopathic scoliosis

    PubMed Central

    2015-01-01

    Background Much attention has been paid to peak height velocity (PHV) as a possible predictor of curve progression in patients with idiopathic scoliosis (IS). The aim of this study was to analyze the relationship between the magnitude of the Cobb angle at PHV and scoliosis progression, defined as having surgery prior to skeletal maturity in female patients with IS. Methods A retrospective review identified 56 skeletally immature female IS patients who were followed until maturity. The mean age and the mean pubertal status at the initial visit were 10 years and 24 months before menarche respectively, with a follow-up period of 5 years. They were divided into two groups: non-surgery group (NS) and surgery group (S), depending on their treatment method in use at the final follow-up visit. Surgery group was defined as an ultimately having surgery due to Cobb angle greater than 45 degrees prior to skeletal maturity regardless of conservative management. Height measurements were recorded at each visit; height velocity was calculated as the height change, in cm, divided by the time interval, in years. The PHV, chronological age at PHV (APHV), height at PHV (HPHV), and final height (FH) were determined for each group. In patients with Cobb angle greater than 30 degrees, the corrected height was calculated by Kono formula and corrected height velocity values were provided. The sensitivity, specificity, and area under the curve (AUC) of the receiver-operating -characteristic (ROC) analysis were calculated to predict spinal curve progression for various Cobb-angle cutoff values at PHV. Results The corrected PHV had a mean value of 8.5 and 8.9 cm/year in the NS-group and S-group, respectively. The APHV was 11.9 and 11 years, the corrected HPHV was 152.9, and 149.3 cm, and the corrected FH was 159.9 and 159.3 cm, respectively. When a Cobb angle of 31.5 degrees was at PHV, ROC analysis revealed 78% sensitivity, 82% specificity, and an AUC of 0.93, acceptable values for curve progression in patients with IS. Conclusions These findings indicate that 31.5 degrees of spinal curvature when patients are at PHV is a significant predictive indicator for progression of the curve to a magnitude requiring surgery. We suggest that the curve-progression risk assessment in patients with IS should include PHV, along with measures of skeletal and non-skeletal maturities. PMID:25815057

  18. [The effectiveness of endonasal electrophoresis of neuroprotective agents used in the rehabilitative treatment of the patients presenting with primary open angle glaucoma].

    PubMed

    Nazarova, G A; Konchugova, T V; Iurova, O V; Sichinava, N V; Turova, E A; Rassulova, M A; Morozova, N E

    2013-01-01

    The objective of the present study was to estimate the effectiveness of the peptide drug cortexin used to treat primary open angle glaucoma. It was shown that endonasal electrophoresis of cortexin resulted in more pronounced positive changes in the dynamics of clinical, functional, perimetric, and electrophysiological characteristics compared with intramuscular administration of the same drug to the patients of the control group. This difference was apparent both immediately after the termination of the treatment and during the long-term follow-up.

  19. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yanagawa, T.; Sakagami, H.; Nagatomo, H.

    In inertial confinement fusion, the implosion process is important in forming a high-density plasma core. In the case of a fast ignition scheme using a cone-guided target, the fuel target is imploded with a cone inserted. This scheme is advantageous for efficiently heating the imploded fuel core; however, asymmetric implosion is essentially inevitable. Moreover, the effect of cone position and opening angle on implosion also becomes critical. Focusing on these problems, the effect of the asymmetric implosion, the initial position, and the opening angle on the compression rate of the fuel is investigated using a three-dimensional pure hydrodynamic code.

  20. [Thinking about the present primary open angle glaucoma early diagnosis concepts and methods].

    PubMed

    Ren, Zeqin

    2014-05-01

    Early diagnosis of primary open-angle glaucoma has not been clear and consistent in concepts and methods. At present, according to the pathophysiology process of optic nerve damage and its detection technology, early diagnosis on the concept still belongs to the early clinical diagnosis instead of preclinical diagnosis, and on the method depends on the fundus as morphological index combined with the visual field as functional index. The direction of early clinical diagnosis mainly lies in exploring more effective diagnosis index, rather than blindly adopt new diagnostic technology.

  1. Open Source 2010: Reflections on 2007

    ERIC Educational Resources Information Center

    Wheeler, Brad

    2007-01-01

    Colleges and universities and commercial firms have demonstrated great progress in realizing the vision proffered for "Open Source 2007," and 2010 will mark even greater progress. Although much work remains in refining open source for higher education applications, the signals are now clear: the collaborative development of software can provide…

  2. 46 CFR 172.195 - Survival conditions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... assumed damage if it meets the following conditions in the final stage of flooding: (a) Final waterline... of an opening through which progressive flooding may take place, such as an air pipe, or an opening... least 3.94 inches (10 cm). (3) Each submerged opening must be weathertight. (d) Progressive flooding. If...

  3. 46 CFR 172.195 - Survival conditions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... assumed damage if it meets the following conditions in the final stage of flooding: (a) Final waterline... of an opening through which progressive flooding may take place, such as an air pipe, or an opening... least 3.94 inches (10 cm). (3) Each submerged opening must be weathertight. (d) Progressive flooding. If...

  4. 46 CFR 172.195 - Survival conditions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... assumed damage if it meets the following conditions in the final stage of flooding: (a) Final waterline... of an opening through which progressive flooding may take place, such as an air pipe, or an opening... least 3.94 inches (10 cm). (3) Each submerged opening must be weathertight. (d) Progressive flooding. If...

  5. Scoliosis in Patients with Severe Cerebral Palsy: Three Different Courses in Adolescents.

    PubMed

    Oda, Yoshiaki; Takigawa, Tomoyuki; Sugimoto, Yoshihisa; Tanaka, Masato; Akazawa, Hirofumi; Ozaki, Toshifumi

    2017-04-01

    Patients with cerebral palsy (CP) frequently present with scoliosis; however, the pattern of curve progression is difficult to predict. We aimed to clarify the natural course of the progression of scoliosis and to identify scoliosis predictors. This was a retrospective, single-center, observational study. Total of 92 CP patients from Asahikawasou Ryouiku Iryou Center in Okayama, Japan were retrospectively analyzed. Cobb angle, presence of hip dislocation and pelvic obliquity, and Gross Motor Function Classification System (GMFCS) were investigated. Severe CP was defined as GMFCS level IV or V. The mean observation period was 10.7 years. Thirtyfour severe CP patients presented with scoliosis and were divided into 3 groups based on their clinical courses: severe, moderate and mild. The mean Cobb angles at the final follow-up were 129°, 53°, and 13° in the severe, moderate, and mild groups, respectively. The average progressions from 18 to 25 years were 2.7°/year, 0.7°/year, and 0.1°/year in the severe, moderate, and mild curve groups, respectively. We observed the natural course of scoliosis and identified 3 courses based on the Cobb angle at 15 and 18 years of age. This method of classification may help clinicians predict the patients' disease progression.

  6. Argon laser peripheral iridoplasty for angle-closure glaucoma in sibilings with weill-marchesani syndrome.

    PubMed

    Ritch, R; Solomon, L D

    1992-01-01

    A patient with Weill-Marchesani syndrome and angle-closure glaucoma had persistent appositional closure after laser iridotomy that was unrelieved by topical application of either miotic or cycloplegic agents. Argon laser peripheral iridoplasty successfully opened the angle. The patient's sister also had Weill-Marchesani syndrome and angle closure unrelieved by laser iridotomy. Angle closure in Weill-Marchesani syndrome and the response to laser iridotomy and treatment with either miotic or cycloplegic agents may be complex and depends on the relative proportion of pupillary block as a mechanism underlying the angle closure, the functional status of the zonular apparatus, and the degree of angle crowding by the peripheral iris in the presence or absence of peripheral anterior synechiae.

  7. Glaucoma and Alzheimer Disease: A Single Age-Related Neurodegenerative Disease of the Brain.

    PubMed

    Mancino, Raffaele; Martucci, Alessio; Cesareo, Massimo; Giannini, Clarissa; Corasaniti, Maria Tiziana; Bagetta, Giacinto; Nucci, Carlo

    2017-12-06

    Open Angle Glaucoma is one of the leading causes of irreversible blindness worldwide. Elevated intraocular pressure is considered an important risk factor for glaucoma, however a subset of patients experience disease progression even in presence of normal intraocular pressure values. This implies that risk factors other than intraocular pressure are involved in the pathogenesis of glaucoma. A possible relationship between glaucoma and neurodegenerative diseases such as Alzheimer Disease has been suggested. In this regard, we have recently described a high prevalence of alterations typical of glaucoma, using Heidelberg Retinal Tomograph-3 (HRT-3), in a group of patients with Alzheimer Disease. Interestingly, these alterations were not associated with elevated intraocular pressure or abnormal Central Corneal Thickness values. Alzheimer Disease is the most common form of dementia associated with progressive deterioration of memory and cognition. Complaints related to vision are common among Alzheimer Disease patients. Features common to both diseases, including risk factors and pathophysiological mechanisms, gleaned from the recent literature do suggest that Alzheimer Disease and glaucoma can be considered age-related neurodegenerative diseases that may co-exist in the elderly. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. Equilibrium configurations of the conducting liquid surface in a nonuniform electric field

    NASA Astrophysics Data System (ADS)

    Zubarev, N. M.; Zubareva, O. V.

    2011-01-01

    Possible equilibrium configurations of the free surface of a conducting liquid deformed by a nonuniform external electric field are investigated. The liquid rests on an electrode that has the shape of a dihedral angle formed by two intersecting equipotential half-planes (conducting wedge). It is assumed that the problem has plane symmetry: the surface is invariant under shift along the edge of the dihedral angle. A one-parametric family of exact solutions for the shape of the surface is found in which the opening angle of the region above the wedge serves as a parameter. The solutions are valid when the pressure difference between the inside and outside of the liquid is zero. For an arbitrary pressure difference, approximate solutions to the problem are constructed and it is demonstrated the approximation error is small. It is found that, when the potential difference exceeds a certain threshold value, equilibrium solutions are absent. In this case, the region occupied by the liquid disintegrates, the disintegration scenario depending on the opening angle.

  9. Optimum take-off angle in the long jump.

    PubMed

    Linthorne, Nicholas P; Guzman, Maurice S; Bridgett, Lisa A

    2005-07-01

    In this study, we found that the optimum take-off angle for a long jumper may be predicted by combining the equation for the range of a projectile in free flight with the measured relations between take-off speed, take-off height and take-off angle for the athlete. The prediction method was evaluated using video measurements of three experienced male long jumpers who performed maximum-effort jumps over a wide range of take-off angles. To produce low take-off angles the athletes used a long and fast run-up, whereas higher take-off angles were produced using a progressively shorter and slower run-up. For all three athletes, the take-off speed decreased and the take-off height increased as the athlete jumped with a higher take-off angle. The calculated optimum take-off angles were in good agreement with the athletes' competition take-off angles.

  10. Wide angle view of the Flight control room of Mission control center

    NASA Image and Video Library

    1984-10-06

    Wide angle view of the flight control room (FCR) of the Mission Control Center (MCC). Some of the STS 41-G crew can be seen on a large screen at the front of the MCC along with a map tracking the progress of the orbiter.

  11. Detection of primary angle closure using anterior segment optical coherence tomography in Asian eyes.

    PubMed

    Nolan, Winifred P; See, Jovina L; Chew, Paul T K; Friedman, David S; Smith, Scott D; Radhakrishnan, Sunita; Zheng, Ce; Foster, Paul J; Aung, Tin

    2007-01-01

    To evaluate noncontact anterior segment optical coherence technology (AS-OCT) as a qualitative method of imaging the anterior chamber angle and to determine its ability to detect primary angle closure when compared with gonioscopy in Asian subjects. Prospective observational case series. Two hundred three subjects were recruited from glaucoma clinics in Singapore with diagnoses of primary angle closure, primary open-angle glaucoma, ocular hypertension, or cataract. Both eyes (if eligible) of each patient were included in the study. Exclusion criteria were pseudophakia or previous glaucoma surgery. Images of the nasal, temporal, and inferior angles were obtained with AS-OCT in dark and then light conditions. Gonioscopic angle width was graded using the Spaeth classification for each quadrant in low lighting conditions. Angle closure was defined by AS-OCT as contact between the peripheral iris and angle wall anterior to the scleral spur and by gonioscopy as a Spaeth grade of 0 degree (posterior trabecular meshwork not visible). Comparison of the 2 methods in detecting angle closure was done by eye and by individual. Sensitivities and specificities of AS-OCT were calculated using gonioscopy as the reference standard. Complete data were available for 342 eyes of 200 patients. Of the patients, 70.9% had a clinical diagnosis of treated or untreated primary angle closure. Angle closure in > or =1 quadrants was detected by AS-OCT in 142 (71%) patients (228 [66.7%] eyes) and by gonioscopy in 99 (49.5%) patients (152 [44.4%] eyes). The inferior angle was closed more frequently than the nasal or temporal quadrants using both AS-OCT and gonioscopy. When performed under dark conditions, AS-OCT identified 98% of those subjects found to have angle closure on gonioscopy (95% confidence interval [CI], 92.2-99.6) and led to the characterization of 44.6% of those found to have open angles on gonioscopy to have angle closure as well. With gonioscopy as the reference standard, specificity of AS-OCT in the dark was 55.4% (95% CI, 45.2-65.2) for detecting individuals with angle closure. Anterior segment OCT is a rapid noncontact method of imaging angle structures. It is highly sensitive in detecting angle closure when compared with gonioscopy. More persons are found to have closed angles with AS-OCT than with gonioscopy.

  12. Ocular Pseudoexfoliation and Cardiovascular Disease: A National Cross-Section Comparison Study

    PubMed Central

    French, Dustin D; Margo, Curtis E; Harman, Lynn E

    2012-01-01

    Background: Pseudoexfoliation is a systemic disorder characterized by the deposition of extracellular matrix material. The microfibrillar material that gives rise to the condition is visible clinically in the anterior segment of the eye, and is also found in other tissues, including blood vessels, skin, gallbladder, kidneys, lungs, and heart. Aims: The present study aims to determine whether ocular pseudoexfoliation is associated with selected cardiovascular diseases. Materials and Methods: A cross-section comparison study was conducted with the help of the Veterans Health Administration databases, using the International Classification of Diseases, Ninth revision, Clinical Modification for pseudoexfoliation of lens capsule and pseudoexfoliation glaucoma. Selected cardiovascular diseases and risk factors for cardiovascular disease were identified using the appropriate medical codes. Patients with primary open-angle glaucoma, chronic sinusitis, and benign prostatic hyperplasia served as the comparison groups. A logistic regression model was used to control for age, gender, race, and major cardiovascular risk factors. Results: There were 6,046 case patients with pseudoexfoliation; approximately half were diagnosed with pseudoexfoliation glaucoma. Various stages of ischemic heart disease, cardiomyopathy, and aortic aneurysm were significantly associated with ocular pseudoexfoliation, after controlling for age, gender, race, and major cardiovascular risk factors. Associations, in general, were less demonstrable relative to the primary open-angle glaucoma comparison group. Conclusion: Associations of ocular pseudoexfoliation with cardiovascular diseases were generally fewer and less pronounced when compared to patients with primary open-angle glaucoma. These results add to the results of earlier studies, which suggest that open-angle glaucoma itself might be a risk factor for certain cardiovascular disorders. PMID:23112968

  13. Comparison between visual field defect in pigmentary glaucoma and primary open-angle glaucoma.

    PubMed

    Nilforushan, Naveed; Yadgari, Maryam; Jazayeri, Anisalsadat

    2016-10-01

    To compare visual field defect patterns between pigmentary glaucoma and primary open-angle glaucoma. Retrospective, comparative study. Patients with diagnosis of primary open-angle glaucoma (POAG) and pigmentary glaucoma (PG) in mild to moderate stages were enrolled in this study. Each of the 52 point locations in total and pattern deviation plot (excluding 2 points adjacent to blind spot) of 24-2 Humphrey visual field as well as six predetermined sectors were compared using SPSS software version 20. Comparisons between 2 groups were performed with the Student t test for continuous variables and the Chi-square test for categorical variables. Thirty-eight eyes of 24 patients with a mean age of 66.26 ± 11 years (range 48-81 years) in the POAG group and 36 eyes of 22 patients with a mean age of 50.52 ± 11 years (range 36-69 years) in the PG group were studied. (P = 0.00). More deviation was detected in points 1, 3, 4, and 32 in total deviation (P = 0.03, P = 0.015, P = 0.018, P = 0.023) and in points 3, 4, and 32 in pattern deviation (P = 0.015, P = 0.049, P = 0.030) in the POAG group, which are the temporal parts of the field. It seems that the temporal area of the visual field in primary open-angle glaucoma is more susceptible to damage in comparison with pigmentary glaucoma.

  14. Macular Thickness Variability in Primary Open Angle Glaucoma Patients using Optical Coherence Tomography

    PubMed Central

    Agarwal, Prakashchand; Sathyan, P; Saini, VK

    2014-01-01

    ABSTRACT Aim: To compare the difference of retinal macular thickness and macular volume using optical coherence tomography (OCT) in primary open angle glaucoma (POAG) patients with the normal subjects. Materials and methods: This observational case control study included primary open angle glaucoma (POAG) patients (n = 124 eyes) and healthy subjects in the control group (n = 124 eyes). All subjects underwent detailed history, general and systemic exami -nation. Complete ocular examination included best corrected visual acuity (BCVA), slit lamp examination, intraocular pressure (IOP), central corneal thickness, gonioscopy, dilated fundus biomicroscopy. Field analysis was done by white on white Humphrey Field Analyzer (Carl Zeiss). Optical coherence tomography imaging of macular area was performed using Stratus OCT (OCT 3, Version 4, Carl Zeiss Inc, Dublin, California, USA). In both these groups, parameters analyzed were macular thickness, inner macular thicknesses (IMT), outer macular thicknesses (OMT), central macular thick ness (CMT) and total macular volume (TMV). Results: The POAG group had significantly decreased values of TMV, OMT and IMT, compared to control group, while there was no difference in CMT, presumably due to absence of ganglion cells in the central part. Thus, macular thickness and volume parameters may be used for making the diagnosis of glaucoma especially in patients with abnormalities of disc. Conclusion: Macular thickness parameters correlated well with the diagnosis of glaucoma. How to cite this article: Sharma A, Agarwal P, Sathyan P, Saini VK. Macular Thickness Variability in Primary Open Angle Glaucoma Patients using Optical Coherence Tomography. J Current Glau Prac 2014;8(1):10-14. PMID:26997801

  15. Glymphatic stasis at the site of the lamina cribrosa as a potential mechanism underlying open-angle glaucoma.

    PubMed

    Wostyn, Peter; Killer, Hanspeter Esriel; De Deyn, Peter Paul

    2017-07-01

    The underlying pathophysiology of primary open-angle glaucoma remains unclear, but the lamina cribrosa seems to be the primary site of injury, and raised intraocular pressure is a major risk factor. In recent years, a decreased intracranial pressure, leading to an abnormally high trans-lamina cribrosa pressure difference, has gained interest as a new risk factor for glaucoma. New research now lends support to the hypothesis that a paravascular transport system is present in the eye analogous to the recently discovered 'glymphatic system' in the brain, which is a functional waste clearance pathway that promotes elimination of interstitial solutes, including β-amyloid, from the brain along paravascular channels. Given that β-amyloid has been reported to increase by chronic elevation of intraocular pressure in glaucomatous animal models and to cause retinal ganglion cell death, the discovery of a paravascular clearance system in the eye may provide powerful new insights into the pathophysiology of primary open-angle glaucoma. In this review, we provide a new conceptual framework for understanding the pathogenesis of primary open-angle glaucoma, present supporting preliminary data from our own post-mortem study and hypothesize that the disease may result from restriction of normal glymphatic flow at the level of the lamina cribrosa owing to a low intracranial pressure and/or a high trans-lamina cribrosa pressure gradient. If confirmed, this viewpoint could offer new perspectives for the development of novel diagnostic and therapeutic strategies for this devastating disorder. © 2017 Royal Australian and New Zealand College of Ophthalmologists.

  16. Improvement in the medial meniscus posterior shift following anterior cruciate ligament reconstruction.

    PubMed

    Inoue, Hiroto; Furumatsu, Takayuki; Miyazawa, Shinichi; Fujii, Masataka; Kodama, Yuya; Ozaki, Toshifumi

    2018-02-01

    Anterior cruciate ligament (ACL) reconstruction can reduce the risk of developing osteoarthritic knees. The goals of ACL reconstruction are to restore knee stability and reduce post-traumatic meniscal tears and cartilage degradation. A chronic ACL insufficiency frequently results in medial meniscus (MM) injury at the posterior segment. How ACL reconstruction can reduce the deformation of the MM posterior segment remains unclear. In this study, we evaluated the form of the MM posterior segment and anterior tibial translation before and after ACL reconstruction using open magnetic resonance imaging (MRI). Seventeen patients who underwent ACL reconstructions without MM injuries were included in this study. MM deformation was evaluated using open MRI before surgery and 3 months after surgery. We measured medial meniscal length (MML), medial meniscal height (MMH), medial meniscal posterior body width (MPBW), MM-femoral condyle contact width (M-FCW) and posterior tibiofemoral distance (PTFD) at knee flexion angles of 10° and 90°. There were no significant pre- and postoperative differences during a flexion angle of 10°. At a flexion angle of 90°, MML decreased from 43.7 ± 4.5 to 41.4 ± 4.5 mm (P < 0.001), MMH from 7.5 ± 1.4 to 6.9 ± 1.4 mm (P = 0.006), MPBW from 13.1 ± 2.0 to 12.2 ± 1.9 mm (P < 0.001) and M-FCW from 10.0 ± 1.5 to 8.5 ± 1.5 mm (P < 0.001) after ACL reconstruction. The PTFD increased from 2.1 ± 2.8 to 2.7 ± 2.4 mm after ACL reconstruction (P = 0.015). ACL reconstruction affects the contact pattern between the MM posterior segment and medial femoral condyle and can reduce the deformation of the MM posterior segment in the knee-flexed position by reducing abnormal anterior tibial translation. It possibly prevents secondary injury to the MM posterior segment and cartilage that progresses to knee osteoarthritis. IV.

  17. Viscoelasticity of nano-alumina dispersions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rand, B.; Fries, R.

    1996-06-01

    The flow and viscoelastic properties of electrostatically stabilized nano-alumina dispersions have been studied as a function of ionic strength and volume fraction of solids. At low ionic strength the suspensions were deflocculated and showed a transition from viscous to elastic behavior as the solid content increased associated with the onset of double layer interpenetration. The phase transition was progressively shifted to higher solids fractions with increasing ionic strength. At higher ionic strength, above the critical coagulation concentration, the suspensions formed attractive networks characterized by high elasticity. Two independent methods of estimating the effective radius of electrostatically stabilized {open_quotes}soft{close_quotes} particles, a{submore » eff}, are presented based on phase angle data and a modified Dougherty-Krieger equation. The results suggest that a{sub eff} is not constant for a given system but changes with both solids fraction and ionic strength.« less

  18. Alternative therapy in glaucoma management: is there any role?

    PubMed

    Parikh, Rajul S; Parikh, Shefali R

    2011-01-01

    Glaucoma is one of the leading causes of blindness worldwide. Various randomized controlled clinical trials have shown that lowering intraocular pressure (IOP) does reduce progression of primary open-angle glaucoma. However, there is lots of interest in nonpharmacological options that includes lifestyle adjustment and alternative and complementary therapy (ACT). At least 5% glaucoma population uses ACT. Various lifestyle activities like exercise and alcohol can reduce IOP by 1 to 2 mm Hg but would have small effect on glaucoma. The psychological stress can increase IOP. Hypothetically and few studies do show neuroprotective effect (or effect on ocular blood flow) of alcohol, Gingko biloba, bilberry, but the current evidence is weak for its routine use. We must also remember the side effects of 'medications' (e.g., marijuana, alcohol) before promoting as remedy for glaucoma. In current armamentarium of glaucoma management, ACT cannot substitute the conventional treatment available to lower IOP.

  19. Management of exfoliative glaucoma: challenges and solutions.

    PubMed

    Holló, Gábor; Katsanos, Andreas; Konstas, Anastasios Gp

    2015-01-01

    Exfoliative glaucoma is the most common type of secondary open-angle glaucoma worldwide. It is characterized by high intraocular pressure (IOP) and worse 24-hour IOP characteristics. In order to minimize progression, treatment of exfoliative glaucoma has to provide a low long-term mean IOP and good 24-hour IOP control. To achieve these goals, fixed-dose combination eye drops, argon and selective laser trabeculoplasty, and various forms of surgery (trabeculectomy, deep sclerectomy, viscocanalostomy, ab interno trabeculotomy, trabecular aspiration, and cataract surgery) all need to be considered during the long-term management of the disease. Since exfoliative glaucoma is a disease of the elderly, and is frequently associated with systemic vascular disease, interdisciplinary consultations are of great clinical importance. These management aspects and the current medical, laser, and surgical results are covered in this review, with a special focus on the needs of the general ophthalmologist.

  20. Management of exfoliative glaucoma: challenges and solutions

    PubMed Central

    Holló, Gábor; Katsanos, Andreas; Konstas, Anastasios GP

    2015-01-01

    Exfoliative glaucoma is the most common type of secondary open-angle glaucoma worldwide. It is characterized by high intraocular pressure (IOP) and worse 24-hour IOP characteristics. In order to minimize progression, treatment of exfoliative glaucoma has to provide a low long-term mean IOP and good 24-hour IOP control. To achieve these goals, fixed-dose combination eye drops, argon and selective laser trabeculoplasty, and various forms of surgery (trabeculectomy, deep sclerectomy, viscocanalostomy, ab interno trabeculotomy, trabecular aspiration, and cataract surgery) all need to be considered during the long-term management of the disease. Since exfoliative glaucoma is a disease of the elderly, and is frequently associated with systemic vascular disease, interdisciplinary consultations are of great clinical importance. These management aspects and the current medical, laser, and surgical results are covered in this review, with a special focus on the needs of the general ophthalmologist. PMID:26045655

  1. The directivity of the sound radiation from panels and openings.

    PubMed

    Davy, John L

    2009-06-01

    This paper presents a method for calculating the directivity of the radiation of sound from a panel or opening, whose vibration is forced by the incidence of sound from the other side. The directivity of the radiation depends on the angular distribution of the incident sound energy in the room or duct in whose wall or end the panel or opening occurs. The angular distribution of the incident sound energy is predicted using a model which depends on the sound absorption coefficient of the room or duct surfaces. If the sound source is situated in the room or duct, the sound absorption coefficient model is used in conjunction with a model for the directivity of the sound source. For angles of radiation approaching 90 degrees to the normal to the panel or opening, the effect of the diffraction by the panel or opening, or by the finite baffle in which the panel or opening is mounted, is included. A simple empirical model is developed to predict the diffraction of sound into the shadow zone when the angle of radiation is greater than 90 degrees to the normal to the panel or opening. The method is compared with published experimental results.

  2. Evaluation of the Association Between Common Genetic Variants Near the ABCA1 Gene and Primary Angle Closure Glaucoma in a Han Chinese Population.

    PubMed

    Luo, Huaichao; Chen, Yuhong; Ye, Zimeng; Sun, Xinghuai; Shi, Yi; Luo, Qian; Gong, Bo; Shuai, Ping; Yang, Jiyun; Zhou, Yu; Liu, Xiaoqi; Zhang, Kaijiong; Tan, Chang; Li, Yuanfeng; Lin, Ying; Yang, Zhenglin

    2015-10-01

    Recently, three large genome-wide association studies have identified multiple variants associated with primary open angle glaucoma (POAG) near the ABCA1 gene. Considering that POAG and primary angle closure glaucoma (PACG) share many similar clinical manifestations, the present study was conducted to investigate whether these genetic variants were also associated with PACG in a Han Chinese population. A case-control association study of 1122 cases (PACG/PAC) and 1311 normal, matched controls was undertaken. Seven single-nucleotide polymorphisms (SNPs) near the ABCA1 gene, including rs2422493, rs2487042, rs2472496, rs2472493, rs2487032, rs2472459, and rs2472519, were genotyped. Genotype and allele frequencies were assessed using χ² tests. Linkage disequilibrium (LD) structure was analyzed by computer software. Among the SNPs genotyped, no association was observed between these SNPs and PACG. However, we discovered that two haplotypes, CATTTAC (corrected P = 0.048) and CGCCCGC (corrected P = 0.048), remained significantly associated with PACG/PAC after Bonferroni correction. Subjects with the CATTTAC haplotype have a 1.71-fold increased possibility of having PACG/PAC, whereas subjects with the CGCCCGC haplotype have 0.47-fold decreased possibility of developing PACG. Our findings suggest that the genetic backgrounds of PACG and POAG might be different. However, whether or not ABCA1 plays a role in the development of PACG is still not made certain by this study. Thus, further research is needed to find the role of ABCA1 in the progress of PACG.

  3. Vection in patients with glaucoma.

    PubMed

    Tarita-Nistor, Luminita; Hadavi, Shahriar; Steinbach, Martin J; Markowitz, Samuel N; González, Esther G

    2014-05-01

    Large moving scenes can induce a sensation of self-motion in stationary observers. This illusion is called "vection." Glaucoma progressively affects the functioning of peripheral vision, which plays an important role in inducing vection. It is still not known whether vection can be induced in these patients and, if it can, whether the interaction between visual and vestibular inputs is solved appropriately. The aim of this study was to investigate vection responses in patients with mild to moderate open-angle glaucoma. Fifteen patients with mild to moderate glaucoma and 15 age-matched controls were exposed to a random-dot pattern at a short viewing distance and in a dark room. The pattern was projected on a large screen and rotated clockwise with an angular speed of 45 degrees per second to induce a sensation of self-rotation. Vection latency, vection duration, and objective and subjective measures of tilt were obtained in three viewing conditions (binocular, and monocular with each eye). Each condition lasted 2 minutes. Patients with glaucoma had longer vection latencies (p = 0.005) than, but the same vection duration as, age-matched controls. Viewing condition did not affect vection responses for either group. The control group estimated the tilt angle as being significantly larger than the actual maximum tilt angle measured with the tilt sensor (p = 0.038). There was no relationship between vection measures and visual field sensitivity for the glaucoma group. These findings suggest that, despite an altered visual input that delays vection, the neural responses involved in canceling the illusion of self-motion remain intact in patients with mild peripheral visual field loss.

  4. Vision Loss in Older Adults.

    PubMed

    Pelletier, Allen L; Rojas-Roldan, Ledy; Coffin, Janis

    2016-08-01

    Vision loss affects 37 million Americans older than 50 years and one in four who are older than 80 years. The U.S. Preventive Services Task Force concludes that current evidence is insufficient to assess the balance of benefits and harms of screening for impaired visual acuity in adults older than 65 years. However, family physicians play a critical role in identifying persons who are at risk of vision loss, counseling patients, and referring patients for disease-specific treatment. The conditions that cause most cases of vision loss in older patients are age-related macular degeneration, glaucoma, ocular complications of diabetes mellitus, and age-related cataracts. Vitamin supplements can delay the progression of age-related macular degeneration. Intravitreal injection of a vascular endothelial growth factor inhibitor can preserve vision in the neovascular form of macular degeneration. Medicated eye drops reduce intraocular pressure and can delay the progression of vision loss in patients with glaucoma, but adherence to treatment is poor. Laser trabeculoplasty also lowers intraocular pressure and preserves vision in patients with primary open-angle glaucoma, but long-term studies are needed to identify who is most likely to benefit from surgery. Tight glycemic control in adults with diabetes slows the progression of diabetic retinopathy, but must be balanced against the risks of hypoglycemia and death in older adults. Fenofibrate also slows progression of diabetic retinopathy. Panretinal photocoagulation is the mainstay of treatment for diabetic retinopathy, whereas vascular endothelial growth factor inhibitors slow vision loss resulting from diabetic macular edema. Preoperative testing before cataract surgery does not improve outcomes and is not recommended.

  5. An Experimental Investigation on the Generation of a Stable Arch in Granular Materials Using a Developed Trapdoor Apparatus

    NASA Astrophysics Data System (ADS)

    Ahmadi, Ali; Seyedi Hosseininia, Ehsan

    2017-06-01

    This paper discusses the formation of stable arches in granular materials by using a series of laboratory tests. To this aim, a developed trapdoor apparatus is designed to find dimensions of arches formed over the door in cohesionless aggregates. This setup has two new important applications. In order to investigate the maximum width of the opening generated exactly on the verge of failure, the door can be open to an arbitrary size. In addition, the box containing granular materials (or base angle) is able to be set on optional angles from zero to 90 degrees with respect to the horizontal. Therefore, it is possible to understand the effect of different levels of gravity accelerations on the formed arches. It is observed that for all tested granular materials, increasing the door size and decreasing the base angle, both cause to increase the width and height of the arch. Moreover, the shape of all arches is governed by a parabola. Furthermore, the maximum door width is approximately five to 8.6 times the particle size, depending on the internal friction angle of materials and the base angle.

  6. Establishing Age-Adjusted Reference Ranges for Iris-Related Parameters in Open Angle Eyes with Anterior Segment Optical Coherence Tomography

    PubMed Central

    Peterson, Jeffrey R.; Blieden, Lauren S.; Chuang, Alice Z.; Baker, Laura A.; Rigi, Mohammed; Feldman, Robert M.; Bell, Nicholas P.

    2016-01-01

    Purpose Define criteria for iris-related parameters in an adult open angle population as measured with swept source Fourier domain anterior segment optical coherence tomography (ASOCT). Methods Ninety-eight eyes of 98 participants with open angles were included and stratified into 5 age groups (18–35, 36–45, 46–55, 56–65, and 66–79 years). ASOCT scans with 3D mode angle analysis were taken with the CASIA SS-1000 (Tomey Corporation, Nagoya, Japan) and analyzed using the Anterior Chamber Analysis and Interpretation software. Anterior iris surface length (AISL), length of scleral spur landmark (SSL) to pupillary margin (SSL-to-PM), iris contour ratio (ICR = AISL/SSL-to-PM), pupil radius, radius of iris centroid (RICe), and iris volume were measured. Outcome variables were summarized for all eyes and age groups, and mean values among age groups were compared using one-way analysis of variance. Stepwise regression analysis was used to investigate demographic and ocular characteristic factors that affected each iris-related parameter. Results Mean (±SD) values were 2.24 mm (±0.46), 4.06 mm (±0.27), 3.65 mm (±0.48), 4.16 mm (±0.47), 1.14 (±0.04), 1.51 mm2 (±0.23), and 38.42 μL (±4.91) for pupillary radius, RICe, SSL-to-PM, AISL, ICR, iris cross-sectional area, and iris volume, respectively. Both pupillary radius (P = 0.002) and RICe (P = 0.027) decreased with age, while SSL-to-PM (P = 0.002) and AISL increased with age (P = 0.001). ICR (P = 0.54) and iris volume (P = 0.49) were not affected by age. Conclusion This study establishes reference values for iris-related parameters in an adult open angle population, which will be useful for future studies examining the role of iris changes in pathologic states. PMID:26815917

  7. Establishing Age-Adjusted Reference Ranges for Iris-Related Parameters in Open Angle Eyes with Anterior Segment Optical Coherence Tomography.

    PubMed

    Peterson, Jeffrey R; Blieden, Lauren S; Chuang, Alice Z; Baker, Laura A; Rigi, Mohammed; Feldman, Robert M; Bell, Nicholas P

    2016-01-01

    Define criteria for iris-related parameters in an adult open angle population as measured with swept source Fourier domain anterior segment optical coherence tomography (ASOCT). Ninety-eight eyes of 98 participants with open angles were included and stratified into 5 age groups (18-35, 36-45, 46-55, 56-65, and 66-79 years). ASOCT scans with 3D mode angle analysis were taken with the CASIA SS-1000 (Tomey Corporation, Nagoya, Japan) and analyzed using the Anterior Chamber Analysis and Interpretation software. Anterior iris surface length (AISL), length of scleral spur landmark (SSL) to pupillary margin (SSL-to-PM), iris contour ratio (ICR = AISL/SSL-to-PM), pupil radius, radius of iris centroid (RICe), and iris volume were measured. Outcome variables were summarized for all eyes and age groups, and mean values among age groups were compared using one-way analysis of variance. Stepwise regression analysis was used to investigate demographic and ocular characteristic factors that affected each iris-related parameter. Mean (±SD) values were 2.24 mm (±0.46), 4.06 mm (±0.27), 3.65 mm (±0.48), 4.16 mm (±0.47), 1.14 (±0.04), 1.51 mm2 (±0.23), and 38.42 μL (±4.91) for pupillary radius, RICe, SSL-to-PM, AISL, ICR, iris cross-sectional area, and iris volume, respectively. Both pupillary radius (P = 0.002) and RICe (P = 0.027) decreased with age, while SSL-to-PM (P = 0.002) and AISL increased with age (P = 0.001). ICR (P = 0.54) and iris volume (P = 0.49) were not affected by age. This study establishes reference values for iris-related parameters in an adult open angle population, which will be useful for future studies examining the role of iris changes in pathologic states.

  8. Graft Angle its Relationship to Tomato Plant Survival

    USDA-ARS?s Scientific Manuscript database

    Growing plants that can withstand the rigors of open field production is imperative. This study examines the relationship of tensile strength to graft angle and plant survival. Tomato seedlings of ‘FL47’ and ‘Rutgers’ were used as scions on ‘Roma’ rootstock under greenhouse and healing chamber con...

  9. Hydraulic droplet coarsening in open-channel capillaries

    NASA Astrophysics Data System (ADS)

    Warren, Patrick B.

    2016-11-01

    Over a range of liquid-solid contact angles, an open-channel capillary with curved or angled sides can show a maximum in the Laplace pressure as a function of the filling state. Examples include double-angle wedges, grooves scored into flat surfaces, steps on surfaces, and the groove between touching parallel cylinders. The liquid in such a channel exhibits a beading instability if the channel is filled beyond the Laplace pressure maximum. The subsequent droplet coarsening takes place by hydraulic transport through the connecting liquid columns that remain in the groove. A mean-field scaling argument predicts the characteristic droplet radius R ˜t1 /7 , as a function of time t . This is confirmed by one-dimensional simulations of the coarsening kinetics. Some remarks are also made on the spreading kinetics of an isolated drop deposited in such a channel.

  10. Assessing the impacts of canopy openness and flight parameters on detecting a sub-canopy tropical invasive plant using a small unmanned aerial system

    NASA Astrophysics Data System (ADS)

    Perroy, Ryan L.; Sullivan, Timo; Stephenson, Nathan

    2017-03-01

    Small unmanned aerial systems (sUAS) have great potential to facilitate the early detection and management of invasive plants. Here we show how very high-resolution optical imagery, collected from small consumer-grade multirotor UAS platform at altitudes of 30-120 m above ground level (agl), can be used to detect individual miconia (Miconia calvescens) plants in a highly invaded tropical rainforest environment on the island of Hawai'i. The central aim of this research was to determine how overstory vegetation cover, imagery resolution, and camera look-angle impact the aerial detection of known individual miconia plants. For our finest resolution imagery (1.37 cm ground sampling distance collected at 30 m agl), we obtained a 100% detection rate for sub-canopy plants with above-crown openness values >40% and a 69% detection rate for those with >20% openness. We were unable to detect any plants with <10% above crown openness. Detection rates progressively declined with coarser spatial resolution imagery, ending in a 0% detection rate for the 120 m agl flights (ground sampling distance of 5.31 cm). The addition of forward-looking oblique imagery improved detection rates for plants below overstory vegetation, though this effect decreased with increasing flight altitude. While dense overstory canopy cover, limited flight times, and visual line of sight regulations present formidable obstacles for detecting miconia and other invasive plant species, we show that sUAS platforms carrying optical sensors can be an effective component of an integrated management plan within challenging subcanopy forest environments.

  11. Risk of Visual Field Progression in Glaucoma Patients with Progressive Retinal Nerve Fiber Layer Thinning: A 5-Year Prospective Study.

    PubMed

    Yu, Marco; Lin, Chen; Weinreb, Robert N; Lai, Gilda; Chiu, Vivian; Leung, Christopher Kai-Shun

    2016-06-01

    To investigate whether progressive retinal nerve fiber layer (RNFL) thinning is predictive of progressive visual field (VF) loss in glaucoma. Prospective study. A total of 139 primary open-angle glaucoma patients (240 eyes) followed up for ≥5 years. Retinal nerve fiber layer imaging and VF testing were performed at ∼4-month intervals. Progressive RNFL thinning was determined by event analysis (Guided Progression Analysis [GPA]) and trend analysis (Trend-based Progression Analysis [TPA]) of serial registered RNFL thickness maps. VF progression was detected according to the Early Manifest Glaucoma Trial (EMGT) ("likely progression") and pointwise linear regression (PLR) criteria (≥3 contiguous locations with sensitivity change <0 decibels [dB]/year at P < 0.01). Hazard ratios (HRs) for predicting VF progression were calculated by Cox proportional hazard modeling with progressive RNFL thinning as a time-dependent covariate. The specificity of GPA/TPA for detection of RNFL changes was determined by the proportion of eyes with significant RNFL thinning/thickening in 25 normal subjects followed weekly for 8 consecutive weeks and the proportion with significant RNFL thickening in the glaucoma group. The HRs of VF progression. A total of 65 (27.1%) and 117 eyes (48.8%) had progressive RNFL thinning based on GPA and TPA, respectively, and 30 (12.5%) and 39 eyes (16.3%) had VF progression per the EMGT and PLR criteria, respectively, during follow-up. Eyes with progressive RNFL thinning had lower VF survival estimates and a faster decline of visual field index than eyes without. Progressive RNFL thinning predicted the development of VF progression with HRs of 8.44 (95% confidence interval, 3.30-21.61) (EMGT criteria) and 5.11 (2.51-10.42) (PLR criteria) for TPA and 3.95 (1.74-8.93) (EMGT criteria) and 3.81 (1.83-7.92) (PLR criteria) for GPA after controlling for baseline covariates. The specificities of GPA and TPA were 100% (83.4%-100.0%) in the normal group and 81.7% (76.2%-86.4%) and 84.2% (78.9%-88.6%), respectively, in the glaucoma group. Progressive RNFL thinning determined by GPA and TPA is predictive of detectable functional decline in glaucoma. This finding underscores the significance of detecting progressive RNFL thinning and its relevance to initiate or augment treatment for glaucoma patients. Regulatory authorities may consider progressive RNFL thinning as an outcome measure in clinical trials for evaluation of glaucoma treatment. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  12. The Research of the Parallel Computing Development from the Angle of Cloud Computing

    NASA Astrophysics Data System (ADS)

    Peng, Zhensheng; Gong, Qingge; Duan, Yanyu; Wang, Yun

    2017-10-01

    Cloud computing is the development of parallel computing, distributed computing and grid computing. The development of cloud computing makes parallel computing come into people’s lives. Firstly, this paper expounds the concept of cloud computing and introduces two several traditional parallel programming model. Secondly, it analyzes and studies the principles, advantages and disadvantages of OpenMP, MPI and Map Reduce respectively. Finally, it takes MPI, OpenMP models compared to Map Reduce from the angle of cloud computing. The results of this paper are intended to provide a reference for the development of parallel computing.

  13. Measurement of surface tension and viscosity by open capillary techniques

    DOEpatents

    Rye,Robert R. , Yost,Frederick G.

    1998-01-01

    An open-channel capillary is provided, having preferably a v-shaped groove in a flat wettable surface. The groove has timing marks and a source marker in which the specimen to be tested is deposited. The time of passage between the timing marks is recorded, and the ratio of surface tension .gamma. to viscosity .mu. is determined from the equation given below: ##EQU1## where h.sub.0 is the groove depth, .alpha. is the groove angle, .theta. is the liquid/solid contact angle, and t is the flow time. It has been shown by the

  14. The Use of Sun Elevation Angle for Stereogrammetric Boreal Forest Height in Open Canopies

    NASA Technical Reports Server (NTRS)

    Montesano, Paul M.; Neigh, Christopher; Sun, Guoqing; Duncanson, Laura Innice; Van Den Hoek, Jamon; Ranson, Kenneth Jon

    2017-01-01

    Stereogrammetry applied to globally available high resolution spaceborne imagery (HRSI; less than 5 m spatial resolution) yields fine-scaled digital surface models (DSMs) of elevation. These DSMs may represent elevations that range from the ground to the vegetation canopy surface, are produced from stereoscopic image pairs (stereo pairs) that have a variety of acquisition characteristics, and have been coupled with lidar data of forest structure and ground surface elevation to examine forest height. This work explores surface elevations from HRSI DSMs derived from two types of acquisitions in open canopy forests. We (1) apply an automated mass-production stereogrammetry workflow to along-track HRSI stereo pairs, (2) identify multiple spatially coincident DSMs whose stereo pairs were acquired under different solar geometry, (3) vertically co-register these DSMs using coincident spaceborne lidar footprints (from ICESat-GLAS) as reference, and(4) examine differences in surface elevations between the reference lidar and the co-registered HRSI DSMs associated with two general types of acquisitions (DSM types) from different sun elevation angles. We find that these DSM types, distinguished by sun elevation angle at the time of stereo pair acquisition, are associated with different surface elevations estimated from automated stereogrammetry in open canopy forests. For DSM values with corresponding reference ground surface elevation from spaceborne lidar footprints in open canopy northern Siberian Larix forests with slopes less than10, our results show that HRSI DSM acquired with sun elevation angles greater than 35deg and less than 25deg (during snow-free conditions) produced characteristic and consistently distinct distributions of elevation differences from reference lidar. The former include DSMs of near-ground surfaces with root mean square errors less than 0.68 m relative to lidar. The latter, particularly those with angles less than 10deg, show distributions with larger differences from lidar that are associated with open canopy forests whose vegetation surface elevations are captured. Terrain aspect did not have a strong effect on the distribution of vegetation surfaces. Using the two DSM types together, the distribution of DSM-differenced heights in forests (6.0 m, sigma = 1.4 m) was consistent with the distribution of plot-level mean tree heights (6.5m, sigma = 1.2 m). We conclude that the variation in sun elevation angle at time of stereo pair acquisition can create illumination conditions conducive for capturing elevations of surfaces either near the ground or associated with vegetation canopy. Knowledge of HRSI acquisition solar geometry and snow cover can be used to understand and combine stereogrammetric surface elevation estimates to co-register rand difference overlapping DSMs, providing a means to map forest height at fine scales, resolving the vertical structure of groups of trees from spaceborne platforms in open canopy forests.

  15. Influence of Contact Angle, Growth Angle and Melt Surface Tension on Detached Solidification of InSb

    NASA Technical Reports Server (NTRS)

    Wang, Yazhen; Regel, Liya L.; Wilcox, William R.

    2000-01-01

    We extended the previous analysis of detached solidification of InSb based on the moving meniscus model. We found that for steady detached solidification to occur in a sealed ampoule in zero gravity, it is necessary for the growth angle to exceed a critical value, the contact angle for the melt on the ampoule wall to exceed a critical value, and the melt-gas surface tension to be below a critical value. These critical values would depend on the material properties and the growth parameters. For the conditions examined here, the sum of the growth angle and the contact angle must exceed approximately 130, which is significantly less than required if both ends of the ampoule are open.

  16. Glaucoma Progression and its Relationship with Corrected and Uncorrected Intraocular Pressure in Eyes with History of Refractive Corneal Surgery.

    PubMed

    Kwon, Junki; Sung, Kyung Rim; Jo, Jaehyuck; Yang, Sung Ho

    2018-04-20

    To investigate glaucoma progression and its relationship with corrected and uncorrected intraocular pressure (IOP) in patients with a history of refractive corneal surgery (RCS). Totally, 56 eyes of 56 primary open-angle glaucoma patients who had a history of RCS were included. Mean keratometry and central corneal thickness were measured at the time of glaucoma diagnosis. Three IOP measurements, i.e., uncorrected IOP ( UC IOP) and corrected IOP calculated by applying the Kohlhaas ( CK IOP) and Ehlers ( CE IOP) formulas, were used. Participants were categorized into two groups (low-teen [<15 mmHg] and high-teen [≥15 mmHg] groups) according to the mean follow-up IOP, in each of the three IOP measurements. Glaucoma progression was determined based on either structurally or functionally by stereoscopic optic disc/retinal nerve fiber layer photographs or visual field tests. Kaplan-Meier survival curves were compared between the low-teens group and high-teens group for each IOP measurement. Risk factors for glaucoma progression, including uncorrected and corrected IOP measurements, were analyzed using a Cox proportional-hazards model. Among total eyes, glaucoma progression was found in 19 (34%) eyes during 4.3 years of mean follow-up period. Individual values of uncorrected IOP and corrected IOP showed significant differences (p < 0.001). Incidence of glaucoma progression was higher in high-teens group than in low-teens group by corrected IOP values (both Kohlhaas and Ehlers, p = 0.006, 0.003), but not by uncorrected IOP values (p = 0.749). The cumulative probability of glaucoma progression was significantly greater in the high-teens group than in the low-teens group using the Elhers formula determined by Kaplan-Meier analysis (p = 0.030). For glaucoma eyes with history of RCS, high-teen group by corrected mean follow-up IOP showed more glaucoma progression than low-teen group. More intensive IOP-lowering treatment will be required for patient with high-teen follow-up corrected IOP to prevent glaucoma progression.

  17. Incidence and rates of visual field progression after longitudinally measured optic disc change in glaucoma.

    PubMed

    Chauhan, Balwantray C; Nicolela, Marcelo T; Artes, Paul H

    2009-11-01

    To determine whether glaucoma patients with progressive optic disc change have subsequent visual field progression earlier and at a faster rate compared with those without disc change. Prospective, longitudinal, cohort study. Eighty-one patients with open-angle glaucoma. Patients underwent confocal scanning laser tomography and standard automated perimetry every 6 months. The complete follow-up was divided into initial and subsequent periods. Two initial periods-first 3 years (Protocol A) and first half of the total follow-up (Protocol B)-were used, with the respective remainder being the subsequent follow-up. Disc change during the initial follow-up was determined with liberal, moderate, or conservative criteria of the Topographic Change Analysis. Subsequent field progression was determined with significant pattern deviation change in >or=3 locations (criterion used in the Early Manifest Glaucoma Trial). As a control analysis, field change during the initial follow-up was determined with significant pattern deviation change in >or=1, >or=2, or >or=3 locations. Survival time to subsequent field progression, rates of mean deviation (MD) change, and positive and negative likelihood ratios. The median (interquartile range) total follow-up was 11.0 (8.0-12.0) years with 22 (18-24) examinations. More patients had disc changes during the initial follow-up compared with field changes. The mean time to field progression was consistently shorter (protocol A, 0.8-1.7 years; protocol B, 0.3-0.7 years) in patients with prior disc change. In the control analysis, patients with prior field change had statistically earlier subsequent field progression (protocol A, 2.9-3.0 years; protocol B, 0.7-0.9). Similarly, patients with either prior disc or field change always had worse mean rates of subsequent MD change, although the distributions overlapped widely. Patients with subsequent field progression were up to 3 times more likely to have prior disc change compared with those without, and up to 5 times more likely to have prior field change compared with those without. Longitudinally measured optic disc change is predictive of subsequent visual field progression and may be an efficacious end point for functional outcomes in clinical studies and trials in glaucoma.

  18. The role of spinal concave–convex biases in the progression of idiopathic scoliosis

    PubMed Central

    Driscoll, Mark; Moreau, Alain; Villemure, Isabelle; Parent, Stefan

    2009-01-01

    Inadequate understanding of risk factors involved in the progression of idiopathic scoliosis restrains initial treatment to observation until the deformity shows signs of significant aggravation. The purpose of this analysis is to explore whether the concave–convex biases associated with scoliosis (local degeneration of the intervertebral discs, nucleus migration, and local increase in trabecular bone-mineral density of vertebral bodies) may be identified as progressive risk factors. Finite element models of a 26° right thoracic scoliotic spine were constructed based on experimental and clinical observations that included growth dynamics governed by mechanical stimulus. Stress distribution over the vertebral growth plates, progression of Cobb angles, and vertebral wedging were explored in models with and without the biases of concave–convex properties. The inclusion of the bias of concave–convex properties within the model both augmented the asymmetrical loading of the vertebral growth plates by up to 37% and further amplified the progression of Cobb angles and vertebral wedging by as much as 5.9° and 0.8°, respectively. Concave–convex biases are factors that influence the progression of scoliotic curves. Quantifying these parameters in a patient with scoliosis may further provide a better clinical assessment of the risk of progression. PMID:19130096

  19. Radiologic changes of ankle joint after total knee arthroplasty.

    PubMed

    Lee, Jung Hee; Jeong, Bi O

    2012-12-01

    The authors noticed that ankle joint osteoarthritis was not uncommon when lower extremity malalignment, such as a knee varus deformity, was present as a result of severe osteoarthritis of the knee. The purpose of this study was to analyze radiologic changes of the ankle joint after total knee arthroplasty. This study included 142 cases in 110 patients who underwent total knee arthroplasty and were followed for at least 3 years. The varus knee group included 128 cases and the valgus knee group included 14 cases. On anteroposterior standing lower extremity radiographs, varus and valgus angles of the knee were measured preoperatively and at the last follow-up. The angle between the ground surface and the distal tibial plafond as well as the upper talus was also measured. In addition, tibial anterior surface angle, talar tilt, space between the medial malleolar distal tip and the medial articular surface of the talus, and medial tibiotalar joint space of the ankle joint were measured. Out of 142 cases, 50 (35.2%) had arthritis in the ankle before total knee arthroplasty and 31 (21.8%) had newly developed or progressive arthritis after surgery. In particular, the varus knee group demonstrated statistically significant differences in preoperative varus deformity, preoperative talar tilt, and postoperative correction angle between the cases that developed or had progressive arthritis and those that did not show any changes (p < .05). After total knee arthroplasty, arthritis developed or progressed in the ankle of many cases radiographically. In particular, when the preoperative talar tilt increased medial to the ankle or the postoperative correction angle was large, the incidence of arthritis in the ankle joint increased. The authors recommend more cautious follow-up on the symptoms of the ankle joint after total knee arthroplasty.

  20. Ocular surface disease incidence in patients with open-angle glaucoma.

    PubMed

    Radenković, Marija; Stanković-Babić, Gordana; Jovanović, Predrag; Djordjević-Jocić, Jasmina; Trenkić-Božinović, Marija

    2016-01-01

    Ocular surface disease (OSD) is a multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbances, tear film instability with potential damage to the ocular surface, accompanied by increased tear film osmolarity and inflammation of the ocular surface. It is a consequence of disrupted homeostasis of lacrimal functional unit. The main pathogenetic mechanism stems from tear hyperosmolarity and tear film instability. The etiological classification is hyposecretory (Sy-Sjögren and non-Sjögren) and evaporative (extrinsic and intrinsic) form. Delphi panel classification grades disease stages. Antiglaucoma topical therapy causes exacerbation or occurrence of symptoms of dry eye due to main ingredients or preservatives (benzalkonium chloride – BAK), which are dose- and time-dependent. BAK reduces the stability of the lipid layer of tears, the number of goblet cells, induces apoptosis and inflammatory infiltration. The aim of this study was the analysis of the OSD incidence in open-angle glaucoma patients caused by topical medicamentous therapy. Retrospective analysis of examined patients with open-angle glaucoma was used. Increased incidence of moderate and advanced OSD Index degrees in the group of primary open-angle glaucoma (POAG) and pseudoexfoliative glaucoma. According to the Delphi Panel Scale the most common grade is IIb (POAG and pseudoexfoliative glaucoma). Evaporative form of OSD prevailed in all treatment groups. High percentage of dry eye in patients with higher concentrations of preservatives applied was noticed. OSD should be timely diagnosed and treated. Dry eye has an impact on surgical outcome and postoperative visual acuity, and in order to improve patient compliance and quality of life, symptoms of dry eye should be addressed and medications with lower concentrations of preservatives should be applied.

  1. Open wedge high tibial osteotomy using three-dimensional printed models: Experimental analysis using porcine bone.

    PubMed

    Kwun, Jun-Dae; Kim, Hee-June; Park, Jaeyoung; Park, Il-Hyung; Kyung, Hee-Soo

    2017-01-01

    The purpose of this study was to evaluate the usefulness of three-dimensional (3D) printed models for open wedge high tibial osteotomy (HTO) in porcine bone. Computed tomography (CT) images were obtained from 10 porcine knees and 3D imaging was planned using the 3D-Slicer program. The osteotomy line was drawn from the three centimeters below the medial tibial plateau to the proximal end of the fibular head. Then the osteotomy gap was opened until the mechanical axis line was 62.5% from the medial border along the width of the tibial plateau, maintaining the posterior tibial slope angle. The wedge-shaped 3D-printed model was designed with the measured angle and osteotomy section and was produced by the 3D printer. The open wedge HTO surgery was reproduced in porcine bone using the 3D-printed model and the osteotomy site was fixed with a plate. Accuracy of osteotomy and posterior tibial slope was evaluated after the osteotomy. The mean mechanical axis line on the tibial plateau was 61.8±1.5% from the medial tibia. There was no statistically significant difference (P=0.160). The planned and post-osteotomy correction wedge angles were 11.5±3.2° and 11.4±3.3°, and the posterior tibial slope angle was 11.2±2.2° pre-osteotomy and 11.4±2.5° post-osteotomy. There were no significant differences (P=0.854 and P=0.429, respectively). This study showed that good results could be obtained in high tibial osteotomy by using 3D printed models of porcine legs. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Changes in the retrobulbar arterial circulation after decrease of the elevated intraocular pressure in men and women with primary open angle glaucoma.

    PubMed

    Marjanović, Ivan; Martinez, Antonio; Marjanović, Marija; Kontić, Djordje; Hentova-Senćanić, Paraskeva; Marković, Vujica; Bozić, Marija

    2013-01-01

    An altered perfusion of the optic nerve head has been proposed as a pathogenic factor of glaucoma. The aim of this study was to evaluate the changes of the hemodynamic parameters in the retrobulbar arterial circulation after decrease of the elevated intraocular pressure (IOP) in women and men with primary open angle glaucoma. The study included 60 patients (33 males and 27 females) older than 50 years, with diagnosed and treated primary open angle glaucoma (77 eyes of 39 patients had increased IOP, > 25 mm Hg).They were examined at the Clinic of Eye Diseases (complete ophthalmologic exam) and Clinic of Neurology, Clinical Center of Serbia, Belgrade, from December 2009 to December 2010. Imaging of hemodynamic parameters of three retrobulbar arterial vessels: ophthalmic, central retinal and posterior ciliary arteries with color Doppler was performed. Among women, hemodynamic arterial parameter of the peak-systolic velocity was increased in the central retinal artery and decreased in the ophthalmic artery and posterior ciliary arteries; end-diastolic velocity was increased in all three retrobulbar vascular levels; Pourcelot resistivity index was increased, but pulsatility index was decreased in all three vessels. Among men, peak-systolic velocity, end-diastolic velocity and pulsatility index were decreased in all three vessels; resistivity index was increased in the ophthalmic artery, but decreased in the central retinal artery and posterior ciliary arteries. There was a significant change of the ophthalmic artery pulsatility index in women, and the end-diastolic velocity of the ophthalmic artery in men. There was a difference of the retrobulbar arterial circulation between women and men with primary open angle glaucoma after decrease of the elevated intraocular pressure.The role of vascular factors in the supply of the optic disc neuroretinal rim is important.

  3. The association between retinal vascular geometry changes and diabetic retinopathy and their role in prediction of progression – an exploratory study

    PubMed Central

    2014-01-01

    Background The study describes the relationship of retinal vascular geometry (RVG) to severity of diabetic retinopathy (DR), and its predictive role for subsequent development of proliferative diabetic retinopathy (PDR). Methods The research project comprises of two stages. Firstly, a comparative study of diabetic patients with different grades of DR. (No DR: Minimal non-proliferative DR: Severe non-proliferative DR: PDR) (10:10: 12: 19). Analysed RVG features including vascular widths and branching angles were compared between patient cohorts. A preliminary statistical model for determination of the retinopathy grade of patients, using these features, is presented. Secondly, in a longitudinal predictive study, RVG features were analysed for diabetic patients with progressive DR over 7 years. RVG at baseline was examined to determine risk for subsequent PDR development. Results In the comparative study, increased DR severity was associated with gradual vascular dilatation (p = 0.000), and widening of the bifurcating angle (p = 0.000) with increase in smaller-child-vessel branching angle (p = 0.027). Type 2 diabetes and increased diabetes duration were associated with increased vascular width (p = <0.05 In the predictive study, at baseline, reduced small-child vascular width (OR = 0.73 (95% CI 0.58-0.92)), was predictive of future progression to PDR. Conclusions The study findings suggest that RVG alterations can act as novel markers indicative of progression of DR severity and establishment of PDR. RVG may also have a potential predictive role in determining the risk of future retinopathy progression. PMID:25001248

  4. Hip arthroscopy versus open surgical dislocation for femoroacetabular impingement

    PubMed Central

    Zhang, Dagang; Chen, Long; Wang, Guanglin

    2016-01-01

    Abstract Background: This meta-analysis aims to evaluate the efficacy and safety of hip arthroscopy versus open surgical dislocation for treating femoroacetabular impingement (FAI) through published clinical trials. Methods: We conducted a comprehensive literature search using PUBMED, EMBASE, and the Cochrane Central Register of Controlled Trials databases for relevant studies on hip arthroscopy and open surgical dislocation as treatment options for FAI. Results: Compared with open surgical dislocation, hip arthroscopy resulted in significantly higher Nonarthritic Hip Scores (NAHS) at 3- and 12-month follow-ups, a significant improvement in NAHS from preoperation to 3 months postoperation, and a significantly lower reoperation rate. Open surgical dislocation resulted in a significantly improved alpha angle by the Dunn view in patients with cam osteoplasty from preoperation to postoperation, compared with hip arthroscopy. This meta-analysis demonstrated no significant differences in the modified Harris Hip Score, Hip Outcome Score-Activities of Daily Living, or Hip Outcome Score-Sport Specific Subscale at 12 months of follow-up, or in complications (including nerve damage, wound infection, and wound dehiscence). Conclusion: Hip arthroscopy resulted in higher NAHS and lower reoperation rates, but had less improvement in alpha angle in patients with cam osteoplasty, than open surgical dislocation. PMID:27741133

  5. The Opening of the Arctic: Establishing a New Security Perimeter for the United States

    DTIC Science & Technology

    2013-02-14

    Eastern oil is projected to come to an end by 2032. British Petroleum, in its annual energy outlook, predicts growth in biofuel supplies and...Inclination angles for GPS and Galileo satellites are 55 and 56 degrees respectively while GLONASS inclination angles are marginally better at 65

  6. Miniaturized haploscope for testing binocular vision

    NASA Technical Reports Server (NTRS)

    Decker, T. A.

    1973-01-01

    Device can reproduce virtually all binocular stimulus conditions (target configuration, vergence angle, and accommodative distance) used to test binocular performance. All subsystems of electronic controls are open-loop and solid-state-controlled and, with the exception of vergence angle drive, utilize dc stepping motors as prime movers. Arrangement is also made for readouts of each variable.

  7. [Results of the ocular hypertension treatment study and the confocal scanning laser ophthalmoscopy ancillary study and evaluation of the heidelberg retina tomograph].

    PubMed

    Klatt, K; Schmidt, E; Scheuerle, A F

    2008-04-01

    The Ocular Hypertension Treatment Study (OHTS) has shown that analyzing changes of the optic disc configuration is superior to evaluating visual field findings for the early detection of primary open angle glaucoma. The Confocal Scanning Laser Ophthalmoscopy Ancillary Study (CSLO) is the first study to reveal that certain topographic baseline measurements of the optic disc are significantly associated with the development of primary open angle glaucoma in patients with ocular hypertension. An abnormally increased "mean height contour" value proved to be the individual parameter connected with the highest risk. The reliability of the Moorfields Regression Analysis of certain individual sectors during early detection of a primary angle glaucoma is higher than that of the global measurement. The temporal superior and inferior as well as the nasal inferior sectors have the highest positive predictive values and the largest risks in both univariate and multivariate analysis.

  8. Fixed combination of bimatoprost and timolol in patients with primary open-angle glaucoma or ocular hypertension with inadequate IOP adjustment

    PubMed Central

    Brief, Gerrett; Lammich, Tobias; Nagel, Edgar; Pfennigsdorf, Sabine; Spraul, Christoph W; Ho, Selwyn

    2010-01-01

    Objective To assess the efficacy and tolerability of a fixed combination of bimatoprost and timolol (BTFC) in a large patient sample in a clinical setting. Methods In this multicenter, observational, noncontrolled, open-label study, patients (n = 1862) with primary open-angle glaucoma or ocular hypertension were treated with BTFC. Assessments were made at baseline, six weeks, and three months. Results Prior to starting BTFC, 92.3% of patients were taking other ocular hypotensive medications. In the overall group at three months, mean intraocular pressure was reduced from baseline (21.7 ± 4.5 mmHg and 21.8 ± 4.9 mmHg for the right and left eye, respectively) to 16.1 ± 3.0 mmHg for each eye (P < 0.0001). The majority of patients (92%) reported no adverse events. The most commonly reported adverse events (in >1% of patients) were eye irritation, and ocular and conjunctival hyperemia. Adherence to treatment was generally better than (35.4%) or the same as (57.5%) with prior therapy. BTFC tolerability was rated as excellent or good by 92.3% of physicians and 85.8% of patients. Conclusions In a large group of patients with primary open-angle glaucoma or ocular hypertension, treatment with BTFC was associated with consistent reductions in IOP, improved adherence to treatment, and good tolerability. PMID:20957059

  9. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Geltman, S.

    Recent measurements on CO{sub 2}-laser-assisted electron-atom collisions have shown large inconsistencies with the Kroll-Watson formula for small-angle scattering. We have carried out a detailed study to compare the predictions of Kroll-Watson theory (for both single and multimode fields) with those of conventional perturbation theory for stimulated free-free transitions. It is found that for {ital E}{sub 0}/2{omega}{sup 2}{lt}1, where perturbation theory is valid, there are large differences with the Kroll-Watson theory. Comparisons of experimental variations with respect to scattering angle and electron energy show much better agreement with perturbation theory than with Kroll-Watson theory. A study of the angular variations inmore » perturbation theory shows that use of the {open_quote}{open_quote}outgoing{close_quote}{close_quote} wave final state gives much better agreement with experiment than does the {open_quote}{open_quote}ingoing{close_quote}{close_quote} wave final state, which is different from the choice made in early bremsstrahlung theory. {copyright} {ital 1996 The American Physical Society.}« less

  10. Influence of PBL with Open-Book Tests on Knowledge Retention Measured with Progress Tests

    ERIC Educational Resources Information Center

    Heijne-Penninga, M.; Kuks, J. B. M.; Hofman, W. H. A.; Muijtjens, A. M. M.; Cohen-Schotanus, J.

    2013-01-01

    The influence of problem-based learning (PBL) and open-book tests on long-term knowledge retention is unclear and subject of discussion. Hypotheses were that PBL as well as open-book tests positively affect long-term knowledge retention. Four progress test results of fifth and sixth-year medical students (n = 1,648) of three medical schools were…

  11. Anterior chamber angle assessment using gonioscopy and ultrasound biomicroscopy.

    PubMed

    Narayanaswamy, Arun; Vijaya, Lingam; Shantha, B; Baskaran, Mani; Sathidevi, A V; Baluswamy, Sukumar

    2004-01-01

    Comparison of anterior chamber angle measurements using ultrasound biomicroscopy (UBM) and gonioscopy. Five hundred subjects were evaluated for grading of angle width by the Shaffer method. UBM was done in the same group to document angle width, angle opening distance (AOD 500), and anterior chamber depth. Biometric parameters were documented in all subjects. UBM and gonioscopic findings were compared. A study was conducted in 282 men and 218 women with a mean age of 57.32 +/- 12.48 years. Gonioscopic grading was used to segregate occludable (slit-like, grades 1 and 2) from nonoccludable (grades 3 and 4) angles. Subjective assessment by gonioscopy resulted in an overestimation of angle width within the occludable group when compared with values obtained by UBM. This did not affect the segregation of occludable versus nonoccludable angles by gonioscopy. Biometric parameters in eyes with occludable angles were significantly lower in comparison with eyes with nonoccludable angles, except for lens thickness. AOD 500 correlated well with angle width. We concluded that clinical segregation into occludable and nonoccludable angles by an experienced observer using gonioscopy is fairly accurate. However, UBM is required for objective quantification of angles, and AOD 500 can be a reliable and standard parameter to grade angle width.

  12. Simulations of Gamma-Ray Burst Jets in a Stratified External Medium: Dynamics, Afterglow Light Curves, Jet Breaks, and Radio Calorimetry

    NASA Astrophysics Data System (ADS)

    De Colle, Fabio; Ramirez-Ruiz, Enrico; Granot, Jonathan; Lopez-Camara, Diego

    2012-05-01

    The dynamics of gamma-ray burst (GRB) jets during the afterglow phase is most reliably and accurately modeled using hydrodynamic simulations. All published simulations so far, however, have considered only a uniform external medium, while a stratified external medium is expected around long duration GRB progenitors. Here, we present simulations of the dynamics of GRB jets and the resulting afterglow emission for both uniform and stratified external media with ρextvpropr -k for k = 0, 1, 2. The simulations are performed in two dimensions using the special relativistic version of the Mezcal code. Common to all calculations is the initiation of the GRB jet as a conical wedge of half-opening angle θ0 = 0.2 whose radial profile is taken from the self-similar Blandford-McKee solution. The dynamics for stratified external media (k = 1, 2) are broadly similar to those derived for expansion into a uniform external medium (k = 0). The jet half-opening angle is observed to start increasing logarithmically with time (or radius) once the Lorentz factor Γ drops below θ-1 0. For larger k values, however, the lateral expansion is faster at early times (when Γ > θ-1 0) and slower at late times with the jet expansion becoming Newtonian and slowly approaching spherical symmetry over progressively longer timescales. We find that, contrary to analytic expectations, there is a reasonably sharp jet break in the light curve for k = 2 (a wind-like external medium), although the shape of the break is affected more by the viewing angle (for θobs <= θ0) than by the slope of the external density profile (for 0 <= k <= 2). Steeper density profiles (i.e., increasing k values) are found to produce more gradual jet breaks while larger viewing angles cause smoother and later appearing jet breaks. The counterjet becomes visible as it becomes sub-relativistic, and for k = 0 this results in a clear bump-like feature in the light curve. However, for larger k values the jet decelerates more gradually, causing only a mild flattening in the radio light curve that might be hard to discern when k = 2. Late-time radio calorimetry, which makes use of a spherical flow approximation near the non-relativistic transition, is likely to consistently overestimate the true energy by up to a factor of a few for k = 2, but likely to either overpredict or underpredict it by a smaller factor for k = 0, 1.

  13. Camouflage of a high-angle skeletal Class II open-bite malocclusion in an adult after mini-implant failure during treatment.

    PubMed

    Franzotti Sant'Anna, Eduardo; Carneiro da Cunha, Amanda; Paludo Brunetto, Daniel; Franzotti Sant'Anna, Claudia

    2017-03-01

    The treatment of skeletal anterior open-bite malocclusion requires complex orthodontic planning that considers its multifactorial etiology, treatment limitations, and high relapse rates. This case report illustrates a successful treatment approach for a skeletal high-angle Class II malocclusion in an adult with a severe open bite. The treatment consisted of a high-pull headgear therapy after mini-implants failure during fixed orthodontic therapy. Adequate esthetics and function were achieved. Despite its low probability, the unexpected event of mini-implant loosening during complex treatments should be considered. Therefore, classic orthodontic mechanics should be established, especially when treating patients for whom invasive procedures such as miniplates or orthognathic surgery are not available options. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  14. Entry, Descent, and Landing Guidance and Control Approaches to Satisfy Mars Human Mission Landing Criteria

    NASA Technical Reports Server (NTRS)

    Dwyer Cianciolo, Alicia; Powell, Richard W.

    2017-01-01

    Precision landing on Mars is a challenge. All Mars lander missions prior to the 2012 Mars Science Laboratory (MSL) had landing location uncertainty ellipses on the order of hundreds of kilometers. Sending humans to the surface of Mars will likely require multiple landers delivered in close proximity, which will in turn require orders of magnitude improvement in landing accuracy. MSL was the first Mars mission to use an Apollo-derived bank angle guidance to reduce the size of the landing ellipse. It utilized commanded bank angle magnitude to control total range and bank angle reversals to control cross range. A shortcoming of this bank angle guidance is that the open loop phase of flight created by use of bank reversals increases targeting errors. This paper presents a comparison of entry, descent and landing performance for a vehicle with a low lift-to-drag ratio using both bank angle control and an alternative guidance called Direct Force Control (DFC). DFC eliminates the open loop flight errors by directly controlling two forces independently, lift and side force. This permits independent control of down range and cross range. Performance results, evaluated using the Program to Optimize Simulated Trajectories (POST2), including propellant use and landing accuracy, are presented.

  15. Reflectance Spectra of Peacock Feathers and the Turning Angles of Melanin Rods in Barbules.

    PubMed

    Okazaki, Toshio

    2018-02-01

    I analyzed the association between the reflectance spectra and melanin rod arrangement in barbules of the eyespot of peacock feathers. The reflectance spectra from the yellow-green feather of the eyespot indicated double peaks of 430 and 540 nm. The maximum reflectance spectrum of the blue feather was 480 nm, and that of the dark blue feather was 420 nm. The reflectance spectra from brown feathers indicated double peaks of 490 and 610 nm. Transmission electron microscopic analysis confirmed that melanin rods were arranged fanwise in the outer layer toward the barbule tips. In addition, using polarized light microscope, I attempted to determine whether the turning angles of melanin rods in the barbules reflected different colors. The turning angle of the polarizing axis of the barbules was supported by that of the melanin rods, observed using transmission electron microscopic images. To compare the turning angle of melanin rods in the respective barbules, I calculated the opening width of the fanwise melanin rods by dividing the width of the barbules by the turning angle of the polarizing axis of barbules and obtained a positive correlation between the reflectance spectra and opening width of the fanwise melanin rods. Moreover, the widely spreading reflection from the barbules may occur because of the fanwise melanin rod arrangement.

  16. Agreement between gonioscopy and ultrasound biomicroscopy in detecting iridotrabecular apposition.

    PubMed

    Barkana, Yaniv; Dorairaj, Syril K; Gerber, Yariv; Liebmann, Jeffrey M; Ritch, Robert

    2007-10-01

    To assess the agreement between findings obtained at dark-room gonioscopy and ultrasound biomicroscopy (UBM) in the diagnosis of iridotrabecular apposition in light and dark conditions. We enrolled patients with appositional angle closure at dark-room gonioscopy performed using a 1-mm slitlamp beam that did not cross the pupil. Ultrasound biomicroscopic images were acquired in normal room light and subsequently with all room lights off. Images were evaluated for the presence or absence of iris-cornea contact. The angle opening distance at 500 microm was calculated. Iridotrabecular apposition in at least 1 angle quadrant was demonstrated in all 18 eyes at dark-room gonioscopy, 17 eyes (94%) at dark-room UBM, and only 10 eyes (56%) at UBM in room light. Of 18 superior angles that were appositionally closed at dark-room gonioscopy, apposition was demonstrated on UBM images in 16 (89%) in a dark room but only 6 (33%) in room light. Angle opening distance was less during dark-room gonioscopy in all but the nasal quadrant. We found high agreement between gonioscopy and UBM when both are performed in a completely dark room. Our findings support the recommendation that, in routine clinical practice, gonioscopy be performed in a dark room to avoid misdiagnosis of treatable iridotrabecular apposition.

  17. A mathematical method for precisely calculating the radiographic angles of the cup after total hip arthroplasty.

    PubMed

    Zhao, Jing-Xin; Su, Xiu-Yun; Xiao, Ruo-Xiu; Zhao, Zhe; Zhang, Li-Hai; Zhang, Li-Cheng; Tang, Pei-Fu

    2016-11-01

    We established a mathematical method to precisely calculate the radiographic anteversion (RA) and radiographic inclination (RI) angles of the acetabular cup based on anterior-posterior (AP) pelvic radiographs after total hip arthroplasty. Using Mathematica software, a mathematical model for an oblique cone was established to simulate how AP pelvic radiographs are obtained and to address the relationship between the two-dimensional and three-dimensional geometry of the opening circle of the cup. In this model, the vertex was the X-ray beam source, and the generatrix was the ellipse in radiographs projected from the opening circle of the acetabular cup. Using this model, we established a series of mathematical formulas to reveal the differences between the true RA and RI cup angles and the measurements results achieved using traditional methods and AP pelvic radiographs and to precisely calculate the RA and RI cup angles based on post-operative AP pelvic radiographs. Statistical analysis indicated that traditional methods should be used with caution if traditional measurements methods are used to calculate the RA and RI cup angles with AP pelvic radiograph. The entire calculation process could be performed by an orthopedic surgeon with mathematical knowledge of basic matrix and vector equations. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

  18. Handling Qualities of a Capsule Spacecraft During Atmospheric Entry

    NASA Technical Reports Server (NTRS)

    Bilimoria, Karl D.; Mueller, Eric R.

    2010-01-01

    A piloted simulation was conducted to study handling qualities for capsule spacecraft entering the Earth s atmosphere. Eight evaluation pilots, including six pilot astronauts, provided Cooper-Harper ratings, workload ratings, and qualitative comments. The simulation began after descending through the atmospheric entry interface point and continued until the drogue parachutes deployed. There were two categories of piloting tasks, both of which required bank angle control. In one task category, the pilot followed a closed-loop bank angle command computed by the backup guidance system to manage g-loads during entry. In the other task category, the pilot used intuitive rules to determine the desired bank angle independently, based on an open-loop schedule of vertical speed, Mach, and total energy specified at several range-to-target gates along the entry trajectory. Pilots were able to accurately track the bank angle guidance commands and steered the capsule toward the recovery site with essentially the same range error as the benchmark autopilot trajectory albeit with substantially higher propellant usage, and the handling qualities for this task were satisfactory. Another key result was that the complex piloting task of atmospheric entry could be performed satisfactorily, even in the presence of large dispersions, by controlling bank angle to follow a simple open-loop schedule.

  19. HST Multicolor (255-1042 nm) Photometry of Saturn's Main Rings. 1; Radial Profiles, Phase and Opening Angle Variations, and Regional Spectra

    NASA Technical Reports Server (NTRS)

    Cuzzi, Jeffrey N.; French, Richard G.; Dones, Luke; DeVincenzi, Donald (Technical Monitor)

    2001-01-01

    The main rings of Saturn were observed with the Planetary Camera of the WFPC2 instrument on the Hubble Space Telescope (HST) from September 1996 to August 2000 as the'ring opening angle to Earth and Sun increased from 4 deg to 24 deg, with a spread of phase angles between 0.3 deg and 6 deg at each opening angle. The rings were routinely observed in the five HST wideband UBVRI filters (F336W, F439W, F555W, F675W, and F814W) and occasionally in the F255W, F785LP, and F1042M filters. The emphasis in this series of papers will be on radial color (implying compositional) variations. In this first paper we describe the analysis technique and calibration procedure, note revisions in a previously published Voyager ring color data analysis, and present new results based on over 100 HST images. In the 300-600 nm spectral range where the rings are red, the 555nm/336nm ratio increases by about 14% as the phase angle increases from 0.3 deg to 6 deg. This effect, never reported previously for the rings, is significantly larger than the phase reddening which characterizes other icy objects, primarily because of the redness of the rings. However, there is no discernible tendency for color to vary with ring opening angle at a given phase angle, and there is no phase variation of color where the spectrum is flat. We infer from this combination of facts that multiple intraparticle scattering, either in a regolith or between facets of an unusually rough surface, is important in these geometries, but that multiple interparticle scattering in a vertically extended layer is not. Voyager color ratios at a phase angle of 14 deg are compatible with this trend, but calibration uncertainties prevent their use in quantitative modeling. Overall ring-average spectra are compatible with those of earlier work within calibration uncertainties, but ring spectra vary noticeably with region. We refine and subdivide the regions previously defined by others. The variation seen between radial profiles of ratios between different wavelength suggests the presence of multiple compositional components with different radial distributions. We present new radial profiles of far UV color ratio (F336W/F255W) showing, substantial global variations having a different radial structure than seen between 555 and 336nm. We also find evidence for absorption in the 850nm spectral range (a feature previously only weakly indicated in ring-averaged spectra) primarily through its radial variation; it is located primarily in the C ring, where the particles are known to have lower albedo, and is consistent with "interplanetary pollution" of the rings.

  20. Brightness discrimination test is not useful in screening for open angle glaucoma.

    PubMed

    Peter, E; Thomas, R; Muliyil, J

    1996-06-01

    Brightness discrimination test (BDT) is routinely employed to assess asymmetrical optic nerve dysfunction and has been suggested as a screening test for primary open angle glaucoma (POAG). We tested the reliability and validity of BDT in the diagnosis of POAG. The study groups included 34 patients with established primary open angle glaucoma, 20 glaucoma suspects, and 33 age-sex matched controls. Cataract was not an exclusion criterion in these groups. The normal brightness score was determined to be 88% (mean score, 94%-2 SD) in a pilot study. Brightness discrimination test was performed in all subjects by two observers independently. BDT showed an excellent interobserver agreement (weighted Kappa 0.84). The presence of a cataract alone increased the risk of brightness impairment twofold, glaucoma alone increased the risk eightfold, and the presence of both conditions by 17 times compared to those with neither condition. BDT was not a useful test in the diagnosis of POAG (sensitivity 67% and specificity 93%); the ability to detect a significant field defect was also poor (sensitivity 53% and specificity 76%). There was poor association between decreased brightness scores and asymmetrical field defects as determined by the Humphrey's field analyzer (HFA).

  1. Characterizing the “POAGome”: A bioinformatics-driven approach to primary open-angle glaucoma

    PubMed Central

    Danford, Ian D.; Verkuil, Lana D.; Choi, Daniel J.; Collins, David W.; Gudiseva, Harini V.; Uyhazi, Katherine E.; Lau, Marisa K.; Kanu, Levi N.; Grant, Gregory R.; Chavali, Venkata R.M.; O’Brien, Joan M.

    2017-01-01

    Primary open-angle glaucoma (POAG) is a genetically, physiologically, and phenotypically complex neurodegenerative disorder. This study addressed the expanding collection of genes associated with POAG, referred to as the “POAGome.” We used bioinformatics tools to perform an extensive, systematic literature search and compiled 542 genes with confirmed associations with POAG and its related phenotypes (normal tension glaucoma, ocular hypertension, juvenile open-angle glaucoma, and primary congenital glaucoma). The genes were classified according to their associated ocular tissues and phenotypes, and functional annotation and pathway analyses were subsequently performed. Our study reveals that no single molecular pathway can encompass the pathophysiology of POAG. The analyses suggested that inflammation and senescence may play pivotal roles in both the development and perpetuation of the retinal ganglion cell degeneration seen in POAG. The TGF-β signaling pathway was repeatedly implicated in our analyses, suggesting that it may be an important contributor to the manifestation of POAG in the anterior and posterior segments of the globe. We propose a molecular model of POAG revolving around TGF-β signaling, which incorporates the roles of inflammation and senescence in this disease. Finally, we highlight emerging molecular therapies that show promise for treating POAG. PMID:28223208

  2. Oxidative stress markers in patients with primary open-angle glaucoma.

    PubMed

    Ghanem, Asaad A; Arafa, Lamiaa F; El-Baz, Ayman

    2010-04-01

    To investigate the levels of antioxidant enzymes catalase (CAT), glutathione peroxidase (GPO), superoxide dismutase (SOD), and malondialdehyde (MDA) in human eyes with primary open-angle glaucoma (POAG) and to correlate their concentrations with severity of glaucoma. A prospective cases control study. Thirty patients with primary open-angle glaucoma and twenty-five patients with senile cataracts of matched age and gender were included in the study prospectively. Aqueous humor samples were obtained by paracentesis at the time of elective surgery for glaucomatous and cataractous patients. Aqueous humor were analyzed for CAT, GPO, SOD, and MDA status. GPO, SOD, and MDA enzyme levels revealed a high significant increase in aqueous humor of POAG patients with respect to the comparative group of cataract patients (P < 0.001). No significant difference in the activity of CAT enzyme in aqueous humor of POAG and cataract patient (P = 0.201). Significant correlation was found between the MDA enzyme level and severe visual field loss (P < 0.001) in POAG patients. Increased levels of aqueous humor GPO, SOD, and MDA may be associated with POAG. In addition, they may be useful antioxidant enzyme levels in aqueous humor of POAG patients as a result of glaucoma disease and not a cause.

  3. Prospective, non-interventional, multicenter study of the intraocular pressure-lowering effects of prostaglandin analog/prostamide-containing therapies in previously treated patients with open-angle glaucoma or ocular hypertension

    PubMed Central

    Tamçelik, Nevbahar; Izgi, Belgin; Temel, Ahmet; Yildirim, Nilgun; Okka, Mehmet; Özcan, Altan; Yüksel, Nurşen; Elgin, Ufuk; Altan, Çiğdem; Ozer, Baris

    2017-01-01

    Objective The objective of this study was to assess the intraocular pressure (IOP)-lowering efficacy, tolerability, safety, and usage patterns of prostaglandin analog/prostamide (PGA/P)-containing topical ocular hypotensives in ocular hypertension (OHT) and primary open-angle glaucoma in the Turkish clinical setting. Methods This non-interventional, multicenter study enrolled previously treated patients who failed to achieve target IOP (or experienced unacceptable adverse events [AEs]) and were prescribed a PGA/P-containing IOP-lowering agent. Treatment was initiated at baseline (V1), and patients returned at weeks 4–6 (V2) and 8–12 (V3). The primary efficacy measure was the change in IOP from baseline at V3 in each eye. The secondary measures were physician’s assessment of IOP-lowering efficacy, patients (%) reaching target IOP determined at V1, hyperemia score, physician and patient assessment of study treatment tolerability at V3, and AE frequency/severity. A subgroup analysis of patients receiving the most common study treatment was conducted. All analyses were performed using the safety population (patients who received one or more doses and had any data available). Results Of 358 enrolled patients, 60.6% had primary open-angle glaucoma, 29.9% had secondary open-angle glaucoma (protocol amendment), and 13.1% had OHT; 13 patients had multiple diagnoses. At V3, the mean IOP change from baseline was ≥−4.2 mmHg (≥21.1%). IOP met or was lower than the target in 81.7% of patients, 95% exhibited none to mild conjunctival hyperemia (most common AE), and tolerability was rated good/very good by >91.1% of patients and physicians. The results were similar in patients who received the most common study treatment, bimatoprost 0.03%/timolol 0.5% (bim/tim; n=310). Conclusion PGA/P-containing medications, including bim/tim, significantly reduced IOP in previously treated patients with open-angle glaucoma or OHT; most reached their target IOP or an IOP even lower than their target and reported good/very good tolerability. PGA/P-containing medications such as bim/tim should be considered as a safe, effective therapeutic option for Turkish patients who exhibit poor response, tolerance, or adherence to their previous therapy. PMID:28458511

  4. A dynamic study of the anterior cruciate ligament of the knee using an open MRI.

    PubMed

    Guenoun, Daphne; Vaccaro, Julien; Le Corroller, Thomas; Barral, Pierre-Antoine; Lagier, Aude; Pauly, Vanessa; Coquart, Benjamin; Coste, Joel; Champsaur, Pierre

    2017-03-01

    Recent anatomical and radiological studies of the anterior cruciate ligament (ACL) suggest the ACL length and orientation change during knee flexion, and an open MRI sequencing during knee flexion enables a dynamic ACL analysis. This study's goal is to describe a normal ACL using a 1T open MRI and, in particular, variations in length and insertion angles at different degrees of flexion. Twenty-one volunteers with clinically healthy knees received a dynamic MRI with their knees in hyperextension, neutral position, and flexed at 45° and 90° angles. For each position, two radiologists measured the ACL lengths and angles of the proximal insertion between the ACL's anterior edge and the roof of the inter-condylar notch. Additionally, we measured the ACL's and the tibial plateau's distal angle insertion between their anterior edges and then compared these with the nonparametric Wilcoxon test. The ACL had a significant extension between the 90° flexion and all other positions (hyperextension: 31.75 ± 2.5 mm, neutral position: 32.5 ± 2.6 mm, 45°: 35.6 ± 1.6 mm, 90°: 35.6 ± 1.6 mm). There was also a significant increase of the angle insertion between the proximal 90° flexion and all other positions, as well as between hyperextension and bending to 45° (hyperextension: 2.45° ± 3.7°, neutral: 13.4° ± 9.7°, 45°: 33 25 ± 9.3, 90: 51.85° ± 9.3°). Additionally, there is a significant increase in the distal angle insertion for all positions (hyperextension: 133.2° ± 5.4°, neutral position: 134.95° ± 4.4°, 45°: 138.35° ± 5.9°, 90°: 149.15° ± 8.6°). Our study is the first to exhibit that a dynamic MRI has a significant ACL extension in vivo during bending. This concept opens the way for further studies to improve the diagnosis of traumatic ACL injuries using a dynamic MRI.

  5. A method to measure internal contact angle in opaque systems by magnetic resonance imaging.

    PubMed

    Zhu, Weiqin; Tian, Ye; Gao, Xuefeng; Jiang, Lei

    2013-07-23

    Internal contact angle is an important parameter for internal wettability characterization. However, due to the limitation of optical imaging, methods available for contact angle measurement are only suitable for transparent or open systems. For most of the practical situations that require contact angle measurement in opaque or enclosed systems, the traditional methods are not effective. Based upon the requirement, a method suitable for contact angle measurement in nontransparent systems is developed by employing MRI technology. In the Article, the method is demonstrated by measuring internal contact angles in opaque cylindrical tubes. It proves that the method also shows great feasibility in transparent situations and opaque capillary systems. By using the method, contact angle in opaque systems could be measured successfully, which is significant in understanding the wetting behaviors in nontransparent systems and calculating interfacial parameters in enclosed systems.

  6. [Sinus tarsi approach combined with medial distraction technique for treatment of intra-articular calcaneus fractures].

    PubMed

    Zhou, Haichao; Ren, Haoyang; Li, Bing; Yu, Tao; Yang, Yunfeng

    2016-07-08

    ?To discuss the effectiveness of limited open reduction via sinus tarsi approach using medial distraction technique in the treatment of intra-articular calcaneus fractures by comparing with open reduction and internal fixation via extensile L-shaped incision. ?A retrospective analysis was made on the clinical data of 21 patients with intra-articular calcaneus fractures treated by sinus tarsi approach combined with medial distraction technique between April 2013 and November 2014 (minimally invasive group), and 32 patients treated by extensile L-shaped incision approach between June 2012 and September 2014 (extensile incision group). No significant difference was found in gender, age, injury pattern, fracture classification, time from injury to operation, preoperative Böhler angle, Gissane angle, calcaneal varus angle, the ankle and hind-foot score of American Orthopaedic Foot and Ankle Society (AOFAS), and visual analogue scale (VAS) score between 2 groups (P>0.05), which was comparable. The operation time, wound complications, and bone healing time were recorded. The postoperative function was also evaluated by AOFAS score and VAS score. The pre-and post-operative Böhler angle, Gissane angle, and calcaneal varus angle were measured on the X-ray films, and the corrective angle was calculated. ?Sixteen patients were followed up 6-18 months (mean, 11.5 months) in the minimally invasive group, and 23 patients for 6-24 months (mean, 13.5 months) in the extensile incision group. Difference was not significant in operation time between 2 groups (t=0.929, P=0.796). No complication occurred in the minimally invasive group; partial skin flap necrosis occurred in 3 cases of the extensile incision group, was cured after dressing change. There was no loosening of implants or reduction loss in 2 groups at last follow-up. Subtalar joint stiffness occurred in 1 case of the minimally invasive group and 4 cases of the extensile incision group, and 1 patient had discomfort for the implants in the extensile incision group. The bone healing time was (9.9±0.8) weeks in the minimally invasive group, and was (10.1±0.7) weeks in the extensile incision group, showing no significant difference (t=0.613, P=0.845 ). Böhler angle, Gissane angle, calcaneal varus angle, AOFAS score, and VAS score were significantly improved at last follow-up when compared with preoperative values in 2 groups (P<0.05), but there was no significant difference between 2 groups (P>0.05), and the corrective value of angle showed no significant difference between 2 groups (P>0.05). ?Limited open reduction via sinus tarsi approach for intra-articular calcaneus fractures could reduce the incidence of wound complications effectively. Meanwhile, the medial distraction technique is helpful to correct the heel varus deformity.

  7. GDF15 is elevated in mice following retinal ganglion cell death and in glaucoma patients

    PubMed Central

    Ban, Norimitsu; Siegfried, Carla J.; Lin, Jonathan B.; Shui, Ying-Bo; Sein, Julia; Pita-Thomas, Wolfgang; Sene, Abdoulaye; Santeford, Andrea; Gordon, Mae; Lamb, Rachel; Dong, Zhenyu; Kelly, Shannon C.; Cavalli, Valeria; Yoshino, Jun

    2017-01-01

    Glaucoma is the second leading cause of blindness worldwide. Physicians often use surrogate endpoints to monitor the progression of glaucomatous neurodegeneration. These approaches are limited in their ability to quantify disease severity and progression due to inherent subjectivity, unreliability, and limitations of normative databases. Therefore, there is a critical need to identify specific molecular markers that predict or measure glaucomatous neurodegeneration. Here, we demonstrate that growth differentiation factor 15 (GDF15) is associated with retinal ganglion cell death. Gdf15 expression in the retina is specifically increased after acute injury to retinal ganglion cell axons and in a murine chronic glaucoma model. We also demonstrate that the ganglion cell layer may be one of the sources of secreted GDF15 and that GDF15 diffuses to and can be detected in aqueous humor (AH). In validating these findings in human patients with glaucoma, we find not only that GDF15 is increased in AH of patients with primary open angle glaucoma (POAG), but also that elevated GDF15 levels are significantly associated with worse functional outcomes in glaucoma patients, as measured by visual field testing. Thus, GDF15 maybe a reliable metric of glaucomatous neurodegeneration, although further prospective validation studies will be necessary to determine if GDF15 can be used in clinical practice. PMID:28469085

  8. Effectiveness of Chêneau brace treatment for idiopathic scoliosis: prospective study in 79 patients followed to skeletal maturity

    PubMed Central

    2011-01-01

    Background Progressive idiopathic scoliosis can negatively influence the development and functioning of 2-3% of adolescents, with health consequences and economic costs, placing the disease in the centre of interest of the developmental medicine. The aim of this study was to evaluate the effectiveness of Chêneau brace in the management of idiopathic scoliosis. Methods A prospective observational study according to SOSORT and SRS recommendations comprised 79 patients (58 girls and 21 boys) with progressive idiopathic scoliosis, treated with Chêneau brace and physiotherapy, with initial Cobb angle between 20 and 45 degrees, no previous brace treatment, Risser 4 or more at the final evaluation and minimum one year follow-up after weaning the brace. Achieving 50° of Cobb angle was considered surgical recommendation. Results At follow-up 20 patients (25.3%) improved, 18 patients (22.8%) were stable, 31 patients (39.2%) progressed below 50 degrees and 10 patients (12.7%) progressed beyond 50 degrees (2 of these 10 patients progressed beyond 60 degrees). Progression concerned the younger and less skeletally mature patients. Conclusion Conservative treatment with Chêneau orthosis and physiotherapy was effective in halting scoliosis progression in 48.1% of patients. The results of this study suggest that bracing is effective in reducing the incidence of surgery in comparison with natural history. PMID:21266084

  9. Optical sensing of anticoagulation status: Towards point-of-care coagulation testing

    PubMed Central

    Tripathi, Markandey M.; Hajjarian, Zeinab; Van Cott, Elizabeth M.; Nadkarni, Seemantini K.

    2017-01-01

    Anticoagulant overdose is associated with major bleeding complications. Rapid coagulation sensing may ensure safe and accurate anticoagulant dosing and reduce bleeding risk. Here, we report the novel use of Laser Speckle Rheology (LSR) for measuring anticoagulation and haemodilution status in whole blood. In the LSR approach, blood from 12 patients and 4 swine was placed in disposable cartridges and time-varying intensity fluctuations of laser speckle patterns were measured to quantify the viscoelastic modulus during clotting. Coagulation parameters, mainly clotting time, clot progression rate (α-angle) and maximum clot stiffness (MA) were derived from the clot viscoelasticity trace and compared with standard Thromboelastography (TEG). To demonstrate the capability for anticoagulation sensing in patients, blood samples from 12 patients treated with warfarin anticoagulant were analyzed. LSR clotting time correlated with prothrombin and activated partial thromboplastin time (r = 0.57–0.77, p<0.04) and all LSR parameters demonstrated good correlation with TEG (r = 0.61–0.87, p<0.04). To further evaluate the dose-dependent sensitivity of LSR parameters, swine blood was spiked with varying concentrations of heparin, argatroban and rivaroxaban or serially diluted with saline. We observed that anticoagulant treatments prolonged LSR clotting time in a dose-dependent manner that correlated closely with TEG (r = 0.99, p<0.01). LSR angle was unaltered by anticoagulation whereas TEG angle presented dose-dependent diminution likely linked to the mechanical manipulation of the clot. In both LSR and TEG, MA was largely unaffected by anticoagulation, and LSR presented a higher sensitivity to increased haemodilution in comparison to TEG (p<0.01). Our results establish that LSR rapidly and accurately measures the response of various anticoagulants, opening the opportunity for routine anticoagulation monitoring at the point-of-care or for patient self-testing. PMID:28771571

  10. Development and Testing of UCLA's Electron Losses and Fields Investigation (ELFIN) Instrument Payload

    NASA Astrophysics Data System (ADS)

    Wilkins, C.; Bingley, L.; Angelopoulos, V.; Caron, R.; Cruce, P. R.; Chung, M.; Rowe, K.; Runov, A.; Liu, J.; Tsai, E.

    2017-12-01

    UCLA's Electron Losses and Fields Investigation (ELFIN) is a 3U+ CubeSat mission designed to study relativistic particle precipitation in Earth's polar regions from Low Earth Orbit. Upon its 2018 launch, ELFIN will aim to address an important open question in Space Physics: Are Electromagnetic Ion-Cyclotron (EMIC) waves the dominant source of pitch-angle scattering of high-energy radiation belt charged particles into Earth's atmosphere during storms and substorms? Previous studies have indicated these scattering events occur frequently during storms and substorms, and ELFIN will be the first mission to study this process in-situ.Paramount to ELFIN's success is its instrument suite consisting of an Energetic Particle Detector (EPD) and a Fluxgate Magnetometer (FGM). The EPD is comprised of two collimated solid-state detector stacks which will measure the incident flux of energetic electrons from 50 keV to 4 MeV and ions from 50 keV to 300 keV. The FGM is a 3-axis magnetic field sensor which will capture the local magnetic field and its variations at frequencies up to 5 Hz. The ELFIN spacecraft spins perpendicular to the geomagnetic field to provide 16 pitch-angle particle data sectors per revolution. Together these factors provide the capability to address the nature of radiation belt particle precipitation by pitch-angle scattering during storms and substorms.ELFIN's instrument development has progressed into the late Engineering Model (EM) phase and will soon enter Flight Model (FM) development. The instrument suite is currently being tested and calibrated at UCLA using a variety of methods including the use of radioactive sources and applied magnetics to simulate orbit conditions during spin sectoring. We present the methods and test results from instrument calibration and performance validation.

  11. Progressive halo-vest traction preceding posterior occipitocervical instrumented fusion for irreducible atlantoaxial dislocation and basilar invagination.

    PubMed

    Li, Peng; Bao, Deming; Cheng, Huijuan; Meng, Fanshuai; Li, Junwei

    2017-11-01

    Surgical treatment of irreducible atlantoaxial dislocation (IAAD) with basilar invagination (BI) is associated with high rates of severe complications, including mortality. This retrospective study investigated the safety and efficacy of progressive halo-vest traction for IAAD with BI prior to posterior occipitocervical instrumented fusion. Between 2009 and 2013, 39 patients with IAAD with BI underwent preoperative reduction by progressive halo-vest traction for 20.82±4.21days. Instrumented fusion was then performed through a posterior approach. Clinical outcomes were based on pain scale and Japanese Orthopedic Association (JOA) scores. Radiographic analysis evaluated changes in atlantodental distance, McGregor's line violation, spinal canal width at the craniocervical junction, cervicomedullary angle, C2-C7 lordosis angle, and the occiput-C2 angle. Follow-ups ranged from 48 to 96 months. Both atlantodental distance and BI significantly improved in all patients. The rates of complete anatomical reduction were 85% for IAAD, and 95% for BI. Most of the patients reported satisfactory pain relief and improvement in daily activity; the mean JOA scores at baseline and last follow-up were 9.10 and 15.92, respectively. Although complications occurred in 10 patients (25.64%), all of which healed uneventfully. The bony fusion rate was 100%. Progressive halo-vest traction before surgery is safe and effective for reduction of IAAD with BI. The technique we describe is a promising method for treatment of complex craniocervical junction deformity. Copyright © 2017. Published by Elsevier B.V.

  12. Neurovascular structures of the mandibular angle and condyle: a comprehensive anatomical review.

    PubMed

    Yang, Hun-Mu; Won, Sung-Yoon; Kim, Hee-Jin; Hu, Kyung-Seok

    2015-11-01

    Various surgical interventions including esthetic surgery, salivary gland excision, and open reduction of fracture have been performed in the area around the mandibular angle and condyle. This study aimed to comprehensively review the anatomy of the neurovascular structures on the angle and condyle with recent anatomic and clinical research. We provide detailed information about the branching and distributing patterns of the neurovascular structures at the mandibular angle and condyle, with reported data of measurements and proportions from previous anatomical and clinical research. Our report should serve to help practitioners gain a better understanding of the area in order or reduce potential complications during local procedures. Reckless manipulation during mandibular angle reduction could mutilate arterial branches, not only from the facial artery, but also from the external carotid artery. The transverse facial artery and superficial temporal artery could be damaged during approach and incision in the condylar area. The marginal mandibular branch of the facial nerve can be easily damaged during submandibular gland excision or facial rejuvenation treatment. The main trunk of the facial nerve and its upper and lower distinct divisions have been damaged during parotidectomy, rhytidectomy, and open reductions of condylar fractures. By revisiting the information in the present study, surgeons will be able to more accurately prevent procedure-related complications, such as iatrogenic vascular accidents on the mandibular angle and condyle, complete and partial facial palsy, gustatory sweating (Frey syndrome), and traumatic neuroma after parotidectomy.

  13. Trabecular Meshwork Height in Primary Open-Angle Glaucoma Versus Primary Angle-Closure Glaucoma.

    PubMed

    Masis, Marisse; Chen, Rebecca; Porco, Travis; Lin, Shan C

    2017-11-01

    To determine if trabecular meshwork (TM) height differs between primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG) eyes. Prospective, cross-sectional clinical study. Adult patients were consecutively recruited from glaucoma clinics at the University of California, San Francisco, from January 2012 to July 2015. Images were obtained from spectral-domain optical coherence tomography (Cirrus OCT; Carl Zeiss Meditec, Inc, Dublin, California, USA). Univariate and multivariate linear mixed models comparing TM height and glaucoma type were performed to assess the relationship between TM height and glaucoma subtype. Mixed-effects regression was used to adjust for the use of both eyes in some subjects. The study included 260 eyes from 161 subjects, composed of 61 men and 100 women. Mean age was 70 years (SD 11.77). There were 199 eyes (123 patients) in the POAG group and 61 eyes (38 patients) in the PACG group. Mean TM heights in the POAG and PACG groups were 812 ± 13 μm and 732 ± 27 μm, respectively, and the difference was significant in univariate analysis (P = .004) and in multivariate analysis (β = -88.7 [24.05-153.5]; P = .008). In this clinic-based population, trabecular meshwork height is shorter in PACG patients compared to POAG patients. This finding may provide insight into the pathophysiology of angle closure and provide assistance in future diagnosis, prevention, and management of the angle-closure spectrum of disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Personality and HIV Disease Progression: Role of NEO-PI-R Openness, Extraversion, and Profiles of Engagement

    PubMed Central

    O'Cleirigh, Conall; Schneiderman, Neil; Weiss, Alexander; Costa, Paul T.

    2008-01-01

    Objective To examine the role of the big five personality domains (Neuroticism, Extraversion, Openness, Agreeableness, Conscientiousness) and their respective facets and profiles on change in CD4 and log HIV-RNA copies/ml (VL) over 4 years. The examination of psychosocial predictors of disease progression in human immunodeficiency virus (HIV) has focused primarily on depression, coping, and stress, with little attention paid to stable individual differences. Methods A diverse sample of HIV-seropositive patients (n = 104) completed personality assessment (NEO-PI-R), underwent comprehensive psychological assessment and blood samples every 6 months for 4 years. Linear rates of change for CD4 cells and VL were modeled using Hierarchical Linear Modeling controlling for antiretrovirals (time dependent covariate), initial disease status, age, gender, ethnicity, and education. Results Domains that were significantly associated with slower disease progression over 4 years included Openness (CD4, VL), Extraversion (CD4, VL), and Conscientiousness (VL). Facets of the above domains that were significantly related to slower disease progression were assertiveness, positive emotions, and gregariousness (Extraversion); ideas, esthetics (Openness); achievement striving and order (Conscientiousness). In addition, profile analyses suggested personality styles which seem to underscore the importance of remaining engaged (e.g., Creative Interactors (E+O+), Upbeat Optimists (N−E+), Welcomers (E+A+), Go Getters (C+E+), and Directed (N−C+)) had slower disease progression, whereas the “homebody” profile (Low Extraversion-Low Openness) was significantly associated with faster disease progression. Conclusions These results provide good initial evidence of the relationship between personality and disease progression in HIV and suggest protective aspects of profiles of engagement. These finding may help identify those individuals at risk for poorer disease course and specify targets for psychosocial interventions. PMID:18256349

  15. Status of the Multi-Angle SpectroRadiometer Instrument for EOS- AM1 and Its Application to Remote Sensing of Aerosols

    NASA Technical Reports Server (NTRS)

    Diner, D. J.; Abdou, W. A.; Bruegge, C. J.; Conel, J. E.; Kahn, R. A.; Martonchik, J. V.; Paradise, S. R.; West, R. A.

    1995-01-01

    The Multi-Angle Imaging SpectroRadiometer (MISR) is being developed at JPL for the AM1 spacecraft in the Earth Observing System (EOS) series. This paper reports on the progress of instrument fabrication and testing, and it discusses the strategy to use the instrument for studying tropospheric aerosols.

  16. 16 CFR 1500.43 - Method of test for flashpoint of volatile flammable materials by Tagliabue open-cup apparatus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... inches in length, with a right-angle bend 1/2-inch from each end. This wire is placed snugly in holes... form a top when shield is open). The interior of the draft shield shall be painted a flat black...

  17. 16 CFR 1500.43 - Method of test for flashpoint of volatile flammable materials by Tagliabue open-cup apparatus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... inches in length, with a right-angle bend 1/2-inch from each end. This wire is placed snugly in holes... form a top when shield is open). The interior of the draft shield shall be painted a flat black...

  18. Effects of Bracing in Adult With Scoliosis: A Retrospective Study.

    PubMed

    Palazzo, Clémence; Montigny, Jean-Paul; Barbot, Frédéric; Bussel, Bernard; Vaugier, Isabelle; Fort, Didier; Courtois, Isabelle; Marty-Poumarat, Catherine

    2017-01-01

    To assess the effectiveness of bracing in adult with scoliosis. Retrospective cohort study. Outpatients followed in 2 tertiary care hospitals. Adults (N=38) with nonoperated progressive idiopathic or degenerative scoliosis treated by custom-molded lumbar-sacral orthoses, with a minimum follow-up time of 10 years before bracing and 5 years after bracing. Progression was defined as a variation in Cobb angle ≥10° between the first and the last radiograph before bracing. The brace was prescribed to be worn for a minimum of 6h/d. Not applicable. Rate of progression of the Cobb angle before and after bracing measured on upright 3-ft full-spine radiographs. At the moment of bracing, the mean age was 61.3±8.2 years, and the mean Cobb angle was 49.6°±17.7°. The mean follow-up time was 22.0±11.1 years before bracing and 8.7±3.3 years after bracing. For both types of scoliosis, the rate of progression decreased from 1.28°±.79°/y before to .21°±.43°/y after bracing (P<.0001). For degenerative and idiopathic scoliosis, it dropped from 1.47°±.83°/y before to .24°±.43°/y after bracing (P<.0001) and .70°±.06°/y before to .24°±.43°/y after bracing (P=.03), respectively. For the first time, to our knowledge, this study suggests that underarm bracing may be effective in slowing down the rate of progression in adult scoliosis. Further prospective studies are needed to confirm these results. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  19. Prevalence of comorbid retinal disease in patients with glaucoma at an academic medical center.

    PubMed

    Griffith, Joseph F; Goldberg, Jeffrey L

    2015-01-01

    Patients with various retinal diseases and patients who have undergone retinal procedures and surgeries have an increased risk of developing ocular hypertension and glaucoma. Little is known about the epidemiology of comorbid retinal diseases in glaucoma patients. This study evaluated the prevalence of retinal comorbidities in a population of patients with five types of glaucoma. A longitudinal, retrospective study was conducted using International Classification of Disease (ICD-9) billing records from 2003 to 2010 at an academic medical center. Patients were classified as having primary open-angle glaucoma (POAG), low tension open-angle glaucoma (NTG), pigmentary open-angle glaucoma, chronic-angle closure glaucoma (CACG), or pseudoexfoliation glaucoma (PXG) if they had at least three clinic visits with the same ICD-9 code. Patients were classified as having a retinal comorbidity if they had two visits with the same code. Variables were analyzed with the independent t-test, χ (2) test, analysis of variance, or Fisher's exact test. A total of 5,154 patients had glaucoma, and 14.8% of these had a retinal comorbidity. The prevalence of comorbid retinal disease was higher in patients with POAG (15.7%) than in those with NTG (10.7%), PXG (10.1%), or pigmentary open-angle glaucoma (3.7%; P<0.05). Two hundred and two patients had diabetic retinopathy, with POAG patients (4.5%) having a higher prevalence than those with CACG (1.4%) or PXG (0.6%; P<0.001). There were 297 patients who had macular degeneration and both POAG (2.0%) and PXG patients (2.9%) had a higher prevalence of nonexudative macular degeneration than those with CACG (0%; P<0.01). Patients with comorbid retinal disease had a higher prevalence of blindness and low vision than those without comorbid retinal disease (1.97% versus 1.02%, P=0.02). The high prevalence of comorbid retinal disease and the nearly twofold increase in blindness and low vision in this population demonstrate the need for ophthalmologists to determine if patients have multiple etiologies for their vision loss. The higher prevalence of certain retinal diseases in POAG patients may reflect common pathophysiological processes that warrant further investigation.

  20. SU-G-TeP4-03: A Multileaf Collimator Calibration and Quality Assurance Technique Using An Electronic Portal Imaging Device

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lebron, S; Yan, G; Li, J

    2016-06-15

    Purpose: To develop an accurate and quick multileaf collimator (MLC) calibration and quality assurance technique using an electronic portal imaging device (EPID) Methods: The MLC models used include the MLCi and Agility (Elekta Ltd). This technique consists of two 22(L)x10(W) cm{sup 2} fields with 0{sup 0} and 180{sup 0} collimator angles centered to an offset EPID. The MLC opening is estimated by calculating the profile at the image’s center in the image’s horizontal direction. Scans in the image’s vertical direction were calculated every 20 pixels in the inner 70% of estimated MLC opening. The profiles’ edges were fitted with linearmore » equations to determine the image’s rotation angle. Then, crossline profiles were scanned at the center of each leaf taking into account the leaf’s width at isocenter and the rotation angle. The profiles’ edges determine the location of the leaves’ edges and these were subtracted from the reference leaf’s position in order to determine the relative leaf offsets. The edge location of all profiles was determined by using the parameterized gradient of the penumbra region. The technique was tested against an established diode array-based method, and for different MLC systems, patterns, gantry angles, days, energies, beam modalities and MLC openings. Results: The differences between the proposed and established methods were 0.26±0.19mm. The leaf offsets’ deviation was <0.3mm (5 months period). For pattern fields, the differences between predetermined and calculated offsets were 0.18±0.18mm. The leaf offset deviation of measurements with different energies and MLC openings were <0.1mm and <0.3mm, respectively. The differences between offsets of FF and FFF beams were 0.01±0.02mm (<0.07mm). The differences between the offsets at different gantry angles were 0.08±0.15mm. Conclusion: The proposed method proved to be accurate and efficient in calculating the relative leaf offsets. Parameterized field edge is essential to obtain accurate result by eliminating the noise from EPID.« less

  1. Precision determination of electron scattering angle by differential nuclear recoil energy method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liyanage, N.; Saenboonruang, K.

    2015-12-01

    The accurate determination of the scattered electron angle is crucial to electron scattering experiments, both with open-geometry large-acceptance spectrometers and ones with dipole-type magnetic spectrometers for electron detection. In particular, for small central-angle experiments using dipole-type magnetic spectrometers, in which surveys are used to measure the spectrometer angle with respect to the primary electron beam, the importance of the scattering angle determination is emphasized. However, given the complexities of large experiments and spectrometers, the accuracy of such surveys is limited and insufficient to meet demands of some experiments. In this article, we present a new technique for determination of themore » electron scattering angle based on an accurate measurement of the primary beam energy and the principle of differential nuclear recoil. This technique was used to determine the scattering angle for several experiments carried out at the Experimental Hall A, Jefferson Lab. Results have shown that the new technique greatly improved the accuracy of the angle determination compared to surveys.« less

  2. Precision Determination of Electron Scattering Angle by Differential Nuclear Recoil Energy Method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liyanage, Nilanga; Saenboonruang, Kiadtisak

    2015-09-01

    The accurate determination of the scattered electron angle is crucial to electron scattering experiments, both with open-geometry large-acceptance spectrometers and ones with dipole-type magnetic spectrometers for electron detection. In particular, for small central-angle experiments using dipole-type magnetic spectrometers, in which surveys are used to measure the spectrometer angle with respect to the primary electron beam, the importance of the scattering angle determination is emphasized. However, given the complexities of large experiments and spectrometers, the accuracy of such surveys is limited and insufficient to meet demands of some experiments. In this article, we present a new technique for determination of themore » electron scattering angle based on an accurate measurement of the primary beam energy and the principle of differential nuclear recoil. This technique was used to determine the scattering angle for several experiments carried out at the Experimental Hall A, Jefferson Lab. Results have shown that the new technique greatly improved the accuracy of the angle determination compared to surveys.« less

  3. Investigation of a bio-inspired lift-enhancing effector on a 2D airfoil.

    PubMed

    Johnston, Joe; Gopalarathnam, Ashok

    2012-09-01

    A flap mounted on the upper surface of an airfoil, called a 'lift-enhancing effector', has been shown in wind tunnel tests to have a similar function to a bird's covert feathers, which rise off the wing's surface in response to separated flows. The effector, fabricated from a thin Mylar sheet, is allowed to rotate freely about its leading edge. The tests were performed in the NCSU subsonic wind tunnel at a chord Reynolds number of 4 × 10(5). The maximum lift coefficient with the effector was the same as that for the clean airfoil, but was maintained over an angle-of-attack range from 12° to almost 20°, resulting in a very gentle stall behavior. To better understand the aerodynamics and to estimate the deployment angle of the free-moving effector, fixed-angle effectors fabricated out of stiff wood were also tested. A progressive increase in the stall angle of attack with increasing effector angle was observed, with diminishing returns beyond the effector angle of 60°. Drag tests on both the free-moving and fixed effectors showed a marked improvement in drag at high angles of attack. Oil flow visualization on the airfoil with and without the fixed-angle effectors proved that the effector causes the separation point to move aft on the airfoil, as compared to the clean airfoil. This is thought to be the main mechanism by which an effector improves both lift and drag. A comparison of the fixed-effector results with those from the free-effector tests shows that the free effector's deployment angle is between 30° and 45°. When operating at and beyond the clean airfoil's stall angle, the free effector automatically deploys to progressively higher angles with increasing angles of attack. This slows down the rapid upstream movement of the separation point and avoids the severe reduction in the lift coefficient and an increase in the drag coefficient that are seen on the clean airfoil at the onset of stall. Thus, the effector postpones the stall by 4-8° and makes the stall behavior more gentle. The benefits of using the effector could include care-free operations at high angles of attack during perching and maneuvering flight, especially in gusty conditions.

  4. Age-related and sex-related changes in the normal soft tissue profile of native Northern Sudanese subjects: a cross-sectional study.

    PubMed

    Sforza, Chiarella; Dolci, Claudia; Gibelli, Daniele M; Codari, Marina; Pucciarelli, Valentina; Ferrario, Virgilio F; Elamin, Fadil

    2016-02-01

    Information about age-related and sex-related normative measurements of the nasolabial region in native Northern Sudanese subjects is scanty. We have therefore used a hand-held laser scanner to measure nasolabial angles and distances, and collected the 3-dimensional coordinates of seven landmarks on the facial soft tissues from 654 healthy native Northern Sudanese subjects (327 male and 327 female, aged 4-30 years). From these we calculated five angles and two linear distances and took the mean (SD) for age and sex, and compared them using factorial analysis of variance. All measurements analysed were significantly modified by age in both sexes (p < 0.01) except for the distance from the lower lip to Ricketts' E-line. Sex had a significant effect on the mentolabial and maxillary prominence angles and both distances (p < 0.005). Nasal convexity and the interlabial angle became more obtuse with growth, while the nasolabial and mentolabial angles reduced progressively with female subjects having significantly more obtuse mentolabial angles (p < 0.001). The maxillary prominence angle progressively decreased during childhood, and increased after adolescence, with larger values in male subjects. The upper and lower lip distances from Ricketts' E-line were also significantly larger in male subjects (p < 0.003), but the difference reduced with age. Overall, there were several differences when we compared our data with published data for African and white subjects, which points to the need for ethnic-specific data. Measurements collected in the current study could be used for the quantitative description of facial morphology in native Northern Sudanese children, adolescents, and young adults. Copyright © 2015 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  5. Characteristics of a wind-actuated aerodynamic braking device for high-speed trains

    NASA Astrophysics Data System (ADS)

    Takami, H.; Maekawa, H.

    2017-04-01

    To shorten the stopping distance of the high speed trains in case of emergency, we developed a small-sized aerodynamic braking unit without use of the friction between a rail and a wheel. The developed device could actuate a pair of two drag panels with a travelling wind. However, after the drag panel fully opened, vibrational movements of the drag panel characterized by its slight flutter were repeated. In this study, to stabilize the opened panel, matters pertaining to the angle of attack with respect to the drag panel and pertaining to the arrangement of the two panels were examined by a wind tunnel experiment using a scale model. As a result, to stabilize the opened panel and to keep the good performance of the braking device, it is found out that an angle of attack of 75 to 80 degrees is suitable provided that the interval of the two panels is narrow enough.

  6. A predictive factor for acquiring an ideal lower limb realignment after opening-wedge high tibial osteotomy.

    PubMed

    Bito, Haruhiko; Takeuchi, Ryohei; Kumagai, Ken; Aratake, Masato; Saito, Izumi; Hayashi, Riku; Sasaki, Yohei; Aota, Yoichi; Saito, Tomoyuki

    2009-04-01

    Obtaining a correct postoperative limb alignment is an important factor in achieving a successful clinical outcome after an opening-wedge high tibial osteotomy (OWHTO). To better predict some of the aspects that impact upon the clinical outcomes following this procedure, including postoperative correction loss and over correction, we examined the changes in the frontal plane of the lower limb in a cohort of patients who had undergone OWHTO using radiography. Forty-two knees from 33 patients (23 cases of osteoarthritis and 10 of osteonecrosis) underwent a valgus realignment OWHTO procedure and were radiographically assessed for changes that occurred pre- and post-surgery. The mean femorotibial angle (FTA) was found to be 182.1 +/- 2.0 degrees (12 +/- 2.0 anatomical varus angulation) preoperatively and 169.6 +/- 2.4 degrees (10.4 +/- 2.4 anatomical valgus angulation) postoperatively. These measurements thus revealed significant changes in the weight bearing line ratio (WBL), femoral axis angle (FA), tibial axis angle (TA), tibia plateau angle (TP), tibia vara angle (TV) and talar tilt angle (TT) following OWHTO. In contrast, no significant change was found in the weight bearing line angle (WBLA) after these treatments. To assess the relationship between the correction angle and these indexes, 42 knees were divided into the following three groups according to the postoperative FTA; a normal correction group (168 degrees < or = FTA < or = 172 degrees ), an over-correction group (FTA < 168 degrees ), and an under-correction group (FTA > 172 degrees ). There were significant differences in the delta angle [DA; calculated as (pre FTA - post FTA) - (pre TV - post TV)] among each group of patients. Our results thus indicate a negative correlation between the DA and preoperative TA (R(2) = 0.148, p < 0.05). Hence, given that the correction errors in our patients appear to negatively correlate with the preoperative TA, postoperative malalignments are likely to be predictable prior to surgery.

  7. An Exploratory Investigation of the Role of Openness in Relationship Quality among Emerging Adult Chinese Couples

    PubMed Central

    Zhou, Yixin; Wang, Kexin; Chen, Shuang; Zhang, Jianxin; Zhou, Mingjie

    2017-01-01

    This study tested emerging adult couples’ openness and its fit effect on their romantic relationship quality using quadratic polynomial regression and response surface analysis. Participants were 260 emerging adult dyads. Both dyads’ openness and relationship quality were measured. The result showed that (1) female and male openness contribute differently to relationship quality; (2) couples with similar high openness could experience better relationship quality than those with similar low openness traits; and (3) when dyadic openness is dissimilar, it is better to be either relatively high or relatively low than to be moderate. These findings highlight the role of openness in emerging adults’ romantic relationships from a dyadic angle. PMID:28360875

  8. A platform for dynamic simulation and control of movement based on OpenSim and MATLAB.

    PubMed

    Mansouri, Misagh; Reinbolt, Jeffrey A

    2012-05-11

    Numerical simulations play an important role in solving complex engineering problems and have the potential to revolutionize medical decision making and treatment strategies. In this paper, we combine the rapid model-based design, control systems and powerful numerical method strengths of MATLAB/Simulink with the simulation and human movement dynamics strengths of OpenSim by developing a new interface between the two software tools. OpenSim is integrated with Simulink using the MATLAB S-function mechanism, and the interface is demonstrated using both open-loop and closed-loop control systems. While the open-loop system uses MATLAB/Simulink to separately reproduce the OpenSim Forward Dynamics Tool, the closed-loop system adds the unique feature of feedback control to OpenSim, which is necessary for most human movement simulations. An arm model example was successfully used in both open-loop and closed-loop cases. For the open-loop case, the simulation reproduced results from the OpenSim Forward Dynamics Tool with root mean square (RMS) differences of 0.03° for the shoulder elevation angle and 0.06° for the elbow flexion angle. MATLAB's variable step-size integrator reduced the time required to generate the forward dynamic simulation from 7.1s (OpenSim) to 2.9s (MATLAB). For the closed-loop case, a proportional-integral-derivative controller was used to successfully balance a pole on model's hand despite random force disturbances on the pole. The new interface presented here not only integrates the OpenSim and MATLAB/Simulink software tools, but also will allow neuroscientists, physiologists, biomechanists, and physical therapists to adapt and generate new solutions as treatments for musculoskeletal conditions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. A platform for dynamic simulation and control of movement based on OpenSim and MATLAB

    PubMed Central

    Mansouri, Misagh; Reinbolt, Jeffrey A.

    2013-01-01

    Numerical simulations play an important role in solving complex engineering problems and have the potential to revolutionize medical decision making and treatment strategies. In this paper, we combine the rapid model-based design, control systems and powerful numerical method strengths of MATLAB/Simulink with the simulation and human movement dynamics strengths of OpenSim by developing a new interface between the two software tools. OpenSim is integrated with Simulink using the MATLAB S-function mechanism, and the interface is demonstrated using both open-loop and closed-loop control systems. While the open-loop system uses MATLAB/Simulink to separately reproduce the OpenSim Forward Dynamics Tool, the closed-loop system adds the unique feature of feedback control to OpenSim, which is necessary for most human movement simulations. An arm model example was successfully used in both open-loop and closed-loop cases. For the open-loop case, the simulation reproduced results from the OpenSim Forward Dynamics Tool with root mean square (RMS) differences of 0.03° for the shoulder elevation angle and 0.06° for the elbow flexion angle. MATLAB’s variable step-size integrator reduced the time required to generate the forward dynamic simulation from 7.1 s (OpenSim) to 2.9 s (MATLAB). For the closed-loop case, a proportional–integral–derivative controller was used to successfully balance a pole on model’s hand despite random force disturbances on the pole. The new interface presented here not only integrates the OpenSim and MATLAB/Simulink software tools, but also will allow neuroscientists, physiologists, biomechanists, and physical therapists to adapt and generate new solutions as treatments for musculoskeletal conditions. PMID:22464351

  10. [The short nose].

    PubMed

    Levet, Y

    2014-12-01

    Short noses are not only depending on the length of the dorsum, but also if there is a saddle deformity, or a too lower situation of the fronto-nasal angle, or an open naso-labial angle or a rim retraction. All the cases are treated, often with the help of cartilage grafts and with a closed approach. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  11. 3. Elevation view of entire midsection using ultrawide angle lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Elevation view of entire midsection using ultrawide angle lens. Note opened south doors and closed north doors. The following photo WA-203-C-4 is similar except the camera position was moved right to include the slope of the south end. - Puget Sound Naval Shipyard, Munitions Storage Bunker, Naval Ammunitions Depot, South of Campbell Trail, Bremerton, Kitsap County, WA

  12. Three-Dimensional Spinal Morphology Can Differentiate Between Progressive and Nonprogressive Patients With Adolescent Idiopathic Scoliosis at the Initial Presentation

    PubMed Central

    Nault, Marie-Lyne; Mac-Thiong, Jean-Marc; Roy-Beaudry, Marjolaine; Turgeon, Isabelle; deGuise, Jacques; Labelle, Hubert

    2014-01-01

    Study Design. This is a prospective case-control study. Objective. The objective of this study was to compare 3-dimensional (3D) morphological parameters of the spine at the first visit between a nonprogressive (NP) and a progressive (P) group of immature adolescent idiopathic scoliosis (AIS). Summary of Background Data. Prediction of curve progression remains challenging in AIS at the first visit. Prediction of progression is based on curve type, curve magnitude, and skeletal or chronological age. Methods. A prospective cohort of 133 AIS was followed from skeletal immaturity to maturity (mean, 37 mo). The first group was made up of patients with AIS with a minimum 6-degree progression of the major curve between the first and last follow-up (P) (n = 53) and the second group was composed of patients with NP who reached maturity with less than 6-degree progression (n = 81). Computerized measurements were taken on reconstructed 3-dimensional (3D) spine radiographs of the first visit. There were 6 categories of measurements: angle of plane of maximum curvature, Cobb angles (kyphosis, lordosis), 3D wedging (apical vertebra, apical disks), rotation (upper and lower junctional vertebra, apical vertebra, and thoracolumbar junction), torsion, and slenderness (height/width ratio). t tests were also conducted. Results. There was no statistical difference between the 2 groups for age and initial Cobb angle. P presented significant hypokyphosis, and parameters related to rotation presented significant statistical differences between NP and P (plane of maximal curvature, torsion, and apical axial rotation). Depth slenderness also presented statistical differences. Conclusion. This study confirms that even at the initial visit, 3D morphological differences exist between P and NP AIS. It supports the use of 3D reconstructions of the spine in the initial evaluation of AIS to help predict outcome. Level of Evidence: 3 PMID:24776699

  13. Colliding Stellar Winds Structure and X-ray Emission

    NASA Astrophysics Data System (ADS)

    Pittard, J. M.; Dawson, B.

    2018-04-01

    We investigate the structure and X-ray emission from the colliding stellar winds in massive star binaries. We find that the opening angle of the contact discontinuity (CD) is overestimated by several formulae in the literature at very small values of the wind momentum ratio, η. We find also that the shocks in the primary (dominant) and secondary winds flare by ≈20° compared to the CD, and that the entire secondary wind is shocked when η ≲ 0.02. Analytical expressions for the opening angles of the shocks, and the fraction of each wind that is shocked, are provided. We find that the X-ray luminosity Lx∝η, and that the spectrum softens slightly as η decreases.

  14. Efficiency of geometric designs of flexible solar panels: mathematical simulation

    NASA Astrophysics Data System (ADS)

    Marciniak, Malgorzata; Hassebo, Yasser; Enriquez-Torres, Delfino; Serey-Roman, Maria Ignacia

    2017-09-01

    The purpose of this study is to analyze various surfaces of flexible solar panels and compare them to the traditional at panels mathematically. We evaluated the efficiency based on the integral formulas that involve flux. We performed calculations for flat panels with different positions, a cylindrical panel, conical panels with various opening angles and segments of a spherical panel. Our results indicate that the best efficiency per unit area belongs to particular segments of spherically-shaped panels. In addition, we calculated the optimal opening angle of a cone-shaped panel that maximizes the annual accumulation of the sun radiation per unit area. The considered shapes are presented below with a suggestion for connections of the cells.

  15. Acoustic metamaterials with broadband and wide-angle impedance matching

    NASA Astrophysics Data System (ADS)

    Liu, Chenkai; Luo, Jie; Lai, Yun

    2018-04-01

    We propose a general approach to design broadband and wide-angle impedance-matched acoustic metamaterials. Such an unusual acoustic impedance matching characteristic can be well explained by using a spatially dispersive effective medium theory. For demonstrations, we used silicone rubber, which has a huge impedance contrast with water, to design one- and two-dimensional acoustic structures which are almost perfectly impedance matched to water for a wide range of incident angles and in a broad frequency band. Our work opens up an approach to realize extraordinary acoustic impedance matching properties via metamaterial-design techniques.

  16. Proximal opening wedge osteotomy with wedge-plate fixation compared with proximal chevron osteotomy for the treatment of hallux valgus: a prospective, randomized study.

    PubMed

    Glazebrook, Mark; Copithorne, Peter; Boyd, Gordon; Daniels, Timothy; Lalonde, Karl-André; Francis, Patricia; Hickey, Michael

    2014-10-01

    Hallux valgus with an increased intermetatarsal angle is usually treated with a proximal metatarsal osteotomy. The proximal chevron osteotomy is commonly used but is technically difficult. This study compares the proximal opening wedge osteotomy of the first metatarsal with the proximal chevron osteotomy for the treatment of hallux valgus with an increased intermetatarsal angle. This prospective, randomized multicenter (three-center) study was based on the clinical outcome scores of the Short Form-36, the American Orthopaedic Foot & Ankle Society forefoot questionnaire, and the visual analog scale for pain, activity, and patient satisfaction. Subjects were assessed prior to surgery and at three, six, and twelve months postoperatively. Surgeon preference was evaluated based on questionnaires and the operative times required for each procedure. No significant differences were found for any of the patients' clinical outcome measurements between the two procedures. The proximal opening wedge osteotomy was found to lengthen, and the proximal chevron osteotomy was found to shorten, the first metatarsal. The intermetatarsal angles improved (decreased) significantly, from 14.8° ± 3.2° to 9.1° ± 2.9 (mean and standard deviation) after a proximal opening wedge osteotomy and from 14.6° ± 3.9° to 11.3° ± 4.0° after a proximal chevron osteotomy (p < 0.05 for both). Operative time required for performing a proximal opening wedge osteotomy is similar to that required for performing a proximal chevron osteotomy (mean and standard deviation, 67.1 ± 16.5 minutes compared with 69.9 ± 18.6 minutes; p = 0.510). Opening wedge and proximal chevron osteotomies have comparable radiographic outcomes and comparable clinical outcomes for pain, satisfaction, and function. The proximal opening wedge osteotomy lengthens, and the proximal chevron osteotomy shortens, the first metatarsal. The proximal opening wedge osteotomy was subjectively less technically demanding and was preferred by the orthopaedic surgeons in this study. Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.

  17. The effect of changing condition of walking speed on the knee angle of rats with osteoarthritis.

    PubMed

    Nam, Chan-Woo; Kim, Kyoung; Na, Sang-Su

    2017-08-01

    [Purpose] The purpose of this study was to investigate the positive effect of exercise on knee osteoarthritis in rats with osteoarthritis induced by applying effective walking speed when changing speed conditions during walking. [Subjects and Methods] The rats used in this study were male Sprague-Dawley rats weighing 300 g and 7 weeks old, and 20 rats were used. The Osteoarthritis (OA) rats model was induced by MIA (monoiodoacetate). The rats was randomly divided into experimental group (MIA injection group) and control group (normal cell line injection group). Treadmill exercise was provided two groups for 2 weeks, 4 days per week. The knee joint angle of the stance was divided into pre-test and post-test, and each group was subjected to paired sample test. Independent sample t-test was conducted to examine the difference between experimental group and control group. [Results] There were statistically significant changes in the control and experimental groups. The knee angle was changed from 99.70 ± 2.40 to 85.60 ± 2.67 in the control group. The knee angle was changed from 100.96 ± 1.36 to 87.71 ± 1.57 in the experimental group. [Conclusion] In conclusion, the angle of the knee gradually decreases. It is considered a characteristic of progressive osteoarthritis. The change of knee angle was less in the experimental group than in the control group. This means that the stiffness of the joints during the walking exercise was less progressed in the experimental group than in the control group.

  18. The effect of changing condition of walking speed on the knee angle of rats with osteoarthritis

    PubMed Central

    Nam, Chan-Woo; Kim, Kyoung; Na, Sang-Su

    2017-01-01

    [Purpose] The purpose of this study was to investigate the positive effect of exercise on knee osteoarthritis in rats with osteoarthritis induced by applying effective walking speed when changing speed conditions during walking. [Subjects and Methods] The rats used in this study were male Sprague-Dawley rats weighing 300 g and 7 weeks old, and 20 rats were used. The Osteoarthritis (OA) rats model was induced by MIA (monoiodoacetate). The rats was randomly divided into experimental group (MIA injection group) and control group (normal cell line injection group). Treadmill exercise was provided two groups for 2 weeks, 4 days per week. The knee joint angle of the stance was divided into pre-test and post-test, and each group was subjected to paired sample test. Independent sample t-test was conducted to examine the difference between experimental group and control group. [Results] There were statistically significant changes in the control and experimental groups. The knee angle was changed from 99.70 ± 2.40 to 85.60 ± 2.67 in the control group. The knee angle was changed from 100.96 ± 1.36 to 87.71 ± 1.57 in the experimental group. [Conclusion] In conclusion, the angle of the knee gradually decreases. It is considered a characteristic of progressive osteoarthritis. The change of knee angle was less in the experimental group than in the control group. This means that the stiffness of the joints during the walking exercise was less progressed in the experimental group than in the control group. PMID:28878468

  19. Efficacy and tolerability of brinzolamide/brimonidine suspension and prostaglandin analogs in patients previously treated with dorzolamide/timolol solution and prostaglandin analogs.

    PubMed

    Lo, Jonathan S; Pang, Pierre M; Lo, Samuel C

    2016-01-01

    Fixed combination glaucoma medication is increasingly used in glaucoma treatment. There is a lack of comparative study in the literature of non-beta blocker combination agents used adjunctively with a glaucoma agent in a different class. The objective of this study is to evaluate the effect of intraocular pressure (IOP) control and tolerability of non-beta blocker combination suspension with prostaglandin analogs (PGA) in patients with open angle glaucoma who were previously treated with beta blocker combination solution with PGA. Open-label retrospective review of patient records. This study looked at patients with open angle glaucoma taking dorzolamide/timolol solution with PGA that were switched to brinzolamide/brimonidine combination suspension with PGA. This study reviewed the charts of all patients who were at least 21 years old with a clinical diagnosis of open-angle glaucoma or ocular hypertension in at least one eye. Patients needed to have been treated with concomitant use of PGA and dorzolamide/timolol solution for at least one month. Patients using dorzolamide/timolol solution plus PGA with medication related ocular irritation were switched to brinzolamide/brimonidine suspension with the same PGA. Best-corrected visual acuity, ocular hyperemia grading, slit lamp biomicroscopy and Goldmann applanation tonometry measurements, and patient medication preferences were assessed at baseline, 1 month and 3 months. Forty eyes with open angle glaucoma. The mean age of the patients was 68 and 60% were females. The IOP before the switch was 17.2 and 16.5 (P=0.70) following the switch at 3 months. We found a decreasing trend of ocular hyperemia (P=0.064) and strong preference (P=0.011) for non-beta blocker combination suspension but no difference of visual acuity and slit lamp findings. Brinzolamide/brimonidine combination suspension when used adjunctively with PGA is equally effective. Patients in this study reported greatly reduced ocular redness and shorter duration of stinging with non-beta blocker combination suspension. Their preference of it over dorzolamide/timolol combination solution makes it a viable treatment option, particularly for the aging glaucoma patient with comorbidities that restrict the beta blocker use.

  20. Tension Strength, Failure Prediction and Damage Mechanisms in 2D Triaxial Braided Composites with Notch

    NASA Technical Reports Server (NTRS)

    Norman, Timothy L.; Anglin, Colin

    1995-01-01

    The unnotched and notched (open hole) tensile strength and failure mechanisms of two-dimensional (2D) triaxial braided composites were examined. The effect of notch size and notch position were investigated. Damage initiation and propagation in notched and unnotched coupons were also examined. Theory developed to predict the normal stress distribution near an open hole and failure for tape laminated composites was evaluated for its applicability to 2D triaxial braided textile composite materials. Four different fiber architectures were considered; braid angle, yarn and braider size, percentage of longitudinal yarns and braider angle varied. Tape laminates equivalent to textile composites were also constructed for comparison. Unnotched tape equivalents were stronger than braided textiles but exhibited greater notch sensitivity. Notched textiles and tape equivalents have roughly the same strength at large notch sizes. Two common damage mechanisms were found: braider yarn cracking and near notch longitudinal yarn splitting. Cracking was found to initiate in braider yarns in unnotched and notched coupons, and propagate in the direction of the braider yarns until failure. Damage initiation stress decreased with increasing braid angle. No significant differences in prediction of near notch strain between textile and tape equivalents could be detected for small braid angle, but the correlations were weak for textiles with large braid angle. Notch strength could not be predicted using existing anisotropic theory for braided textiles due to their insensitivity to notch.

  1. Practical Tests with the "auto Control Slot." Part II : Discussion

    NASA Technical Reports Server (NTRS)

    Lachmann, G

    1930-01-01

    For some time the D.V.L. has been investigating the question of applicability of Handley Page slotted wings to German airplanes. Comparitive gliding tests were made with open and closed slots on an Albatros L 75 airplane equipped with the Handley Page "auto control slots." This investigation served to determine the effect of the auto control slot on the properties and performances of airplanes at large angles of attack. The most important problems were whether the angle of glide at small angles of attack can be increased by the adoption of the auto control slot and, in particular, as to whether the flight characteristics at large angles of attack are improved thereby and equilibrium in gliding flight is guaranteed even at larger than ordinary angles of attack.

  2. Practical Tests with the "auto Control Slot." Part I : Lecture

    NASA Technical Reports Server (NTRS)

    Lachmann, G

    1930-01-01

    For some time the D.V.L. has been investigating the question of applicability of Handley Page slotted wings to German airplanes. Comparitive gliding tests were made with open and closed slots on an Albatros L 75 airplane equipped with the Handley Page "auto control slots." This investigation served to determine the effect of the auto control slot on the properties and performances of airplanes at large angles of attack. The most important problems were whether the angle of glide at small angles of attack can be increased by the adoption of the auto control slot and, in particular, as to whether the flight characteristics at large angles of attack are improved thereby and equilibrium in gliding flight is guaranteed even at larger than ordinary angles of attack.

  3. Open-loop GPS signal tracking at low elevation angles from a ground-based observation site

    NASA Astrophysics Data System (ADS)

    Beyerle, Georg; Zus, Florian

    2016-04-01

    For more than a decade space-based global navigation satellite system (GNSS) radio occultation (RO) observations are used by meteorological services world-wide for their numerical weather prediction models. In addition, climate studies increasingly rely on validated GNSS-RO data sets of atmospheric parameters. GNSS-RO profiles typically cover an altitude range from the boundary layer up to the upper stratosphere; their highest accuracy and precision, however, are attained at the tropopause level. In the lower troposphere, multipath ray propagation tend to induce signal amplitude and frequency fluctuations which lead to the development and implementation of open-loop signal tracking methods in GNSS-RO receiver firmwares. In open-loop mode the feed-back values for the carrier tracking loop are derived not from measured data, but from a Doppler frequency model which usually is extracted from an atmospheric climatology. In order to ensure that this receiver-internal parameter set, does not bias the carrier phase path observables, dual-channel open-loop GNSS-RO signal tracking was suggested. Following this proposal the ground-based "GLESER" (GPS low-elevation setting event recorder) campaign was established. Its objective was to disproof the existence of model-induced frequency biases using ground-based GPS observations at very low elevation angles. Between January and December 2014 about 2600 validated setting events, starting at geometric elevation angles of +2° and extending to -1°… - 1.5°, were recorded by the single frequency "OpenGPS" GPS receiver at a measurement site located close to Potsdam, Germany (52.3808°N, 13.0642°E). The study is based on the assumption that these ground-based observations may be used as proxies for space-based RO measurements, even if the latter occur on a one order of magnitude faster temporal scale. The "GLESER" data analysis shows that the open-loop Doppler model has negligible influence on the derived frequency profile provided signal-to-noise density ratios remain above about 30 dB Hz. At low signal levels, however, the dual-channel open-loop design, which tracks the same signal using two Doppler models separated by a 10 Hz offset, reveals a notable bias. A significant fraction of this bias is caused by frequency aliasing. The receiver's dual-channel setup, however, allows for unambiguous identification of the affected observation samples. Finally, the repeat patterns in terms of azimuth angle of the GPS orbit traces reveals characteristic signatures in both, signal amplitude and Doppler frequency with respect to the topography close to the observation site. On the other hand, mean vertical refractivity gradients extracted from ECMWF meteorological fields exhibit moderate correlations with observed signal amplitude fluctuations at negative elevation angles emphasizing the information content of low-elevation GPS signals with respect to the atmospheric state in the boundary layer.

  4. Open conformation of a substrate-binding cleft: sup 19 F NMR studies of cleft angle in the D-galactose chemosensory receptor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Luck, L.A.; Falke, J.J.

    1991-07-02

    The Escherichia coli D-galactose and D-glucose receptor is a two-domain structure with a sugar-binding site at the interface between domains. The structure of the closed cleft containing bound D-glucose has been determined crystalloghraphically, but the open cleft remains to be characterized. The present study illustrates a generalizable approach that is used to detect and analyze both the open- and closed-cleft conformations in solution. A {sup 19}F nucleus located inside the cleft is monitored by {sup 19}F NMR. When the cleft is occupied by D-glucose, the {sup 19}F nucleus is found to be inaccessible to the aqueous paramagnetic probe Gd{center dot}EDTA,more » verifying that the occupied cleft is closed in solution and inaccessible to bulk solvent. When the cleft is empty, the {sup 19}F nucleus becomes accessible to the paramagnet such that the distance of closest approach is r {le} 10 {angstrom}, indicating that the empty cleft opens at least transiently by an angle {theta} {ge} 18 {plus minus} 3{degrees}.« less

  5. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mizuta, Akira; Ioka, Kunihito

    We investigate the jet propagation and breakout from the stellar progenitor for gamma-ray burst (GRB) collapsars by performing two-dimensional relativistic hydrodynamic simulations and analytical modeling. We find that the jet opening angle is given by θ{sub j} ∼ 1/5Γ{sub 0} and infer the initial Lorentz factor of the jet at the central engine, Γ{sub 0}, is a few for existing observations of θ{sub j}. The jet keeps the Lorentz factor low inside the star by converging cylindrically via collimation shocks under the cocoon pressure and accelerates at jet breakout before the free expansion to a hollow-cone structure. In this newmore » picture, the GRB duration is determined by the sound crossing time of the cocoon, after which the opening angle widens, reducing the apparent luminosity. Some bursts violating the maximum opening angle θ{sub j,{sub max}} ∼ 1/5 ∼ 12° imply the existence of a baryon-rich sheath or a long-acting jet. We can explain the slopes in both Amati and Yonetoku spectral relations using an off-centered photosphere model, if we make only one assumption that the total jet luminosity is proportional to the initial Lorentz factor of the jet. We also numerically calibrate the pre-breakout model (Bromberg et al.) for later use.« less

  6. Examining Delay Intervals in the Diagnosis and Treatment of Primary Open Angle Glaucoma in an Egyptian Population and Its Impact on Lifestyle

    PubMed Central

    Abu Hussein, Nahla B.; Habib, Ahmed E.; El Sayed, Yasmine M.

    2016-01-01

    Purpose. To examine causes as well as extent of delay in diagnosis and treatment of primary open angle glaucoma patients in a sample of Egyptians. Patients and Methods. 440 patients with primary open angle glaucoma were interviewed to evaluate delay in their diagnosis and treatment. The extent and cause of delay were investigated. The total delay interval, if any, was correlated with socioeconomic and other factors. Results. The median total delay was one year, with 50% of patients having a total delay of 1 year or less, of which 25% exhibited zero total delay. 25% of patients had a delay ranging from 1 to 3 years, and 25% had a total delay ranging from 3 to 27 years. Diagnostic delay accounted for 43.03% of cases. Longer delays were met in patients with certain socioeconomic factors. Patients with a positive family history of glaucoma displayed shorter delay periods. Conclusion. Significant delay in the diagnosis and treatment of glaucoma was found. Poor socioeconomic status seems to hinder timely diagnosis and treatment of POAG. Certain socioeconomic factors seem to correlate with the extent of delay. More effort is thus needed to subsidize the cost of investigations and treatment for glaucoma patients. PMID:28116140

  7. First-line treatment for elevated intraocular pressure (IOP) associated with open-angle glaucoma or ocular hypertension: focus on bimatoprost

    PubMed Central

    Law, Simon K

    2007-01-01

    The goal of treatment for open-angle glaucoma or ocular hypertension is to improve quality of life through reduction of intraocular pressure (IOP) to preserve visual function. Prostaglandins, as a newer class of ocular hypotensive agents, have been shown to be effective in IOP reduction by the primary mechanism of action of increase the uveoscleral outflow. Bimatoprost is a member this class, but different from the other members by having an ethyl amide group rather than an isopropyl ester at the C-1 carbon of the alpha chain. Bimatoprost used once daily has been shown to be more effect in IOP reduction than other classes of topical ocular hypotensive agents including beta-blockers, carbonic anhydrase inhibitors, and alpha agonists. Comparing with other topical prostaglandins, bimatoprost may be slightly more effective in IOP reduction, but the clinical significance is uncertain. The commonly reported adverse events associated with bimatoprost are localized to the eye and include conjunctival hyperemia, changes in the pigmentation of the periocular skin and iris, and eyelash darkening and growth. It is currently approved by the Food and Drug Administration (FDA) and the European Commission (EC) for first-line therapy for the reduction of elevated IOP in patients with open-angle glaucoma or ocular hypertension. PMID:19668476

  8. Spatial hearing in Cope’s gray treefrog: I. Open and closed loop experiments on sound localization in the presence and absence of noise

    PubMed Central

    Caldwell, Michael S.; Bee, Mark A.

    2014-01-01

    The ability to reliably locate sound sources is critical to anurans, which navigate acoustically complex breeding choruses when choosing mates. Yet, the factors influencing sound localization performance in frogs remain largely unexplored. We applied two complementary methodologies, open and closed loop playback trials, to identify influences on localization abilities in Cope’s gray treefrog, Hyla chrysoscelis. We examined localization acuity and phonotaxis behavior of females in response to advertisement calls presented from 12 azimuthal angles, at two signal levels, in the presence and absence of noise, and at two noise levels. Orientation responses were consistent with precise localization of sound sources, rather than binary discrimination between sources on either side of the body (lateralization). Frogs were unable to discriminate between sounds arriving from forward and rearward directions, and accurate localization was limited to forward sound presentation angles. Within this region, sound presentation angle had little effect on localization acuity. The presence of noise and low signal-to-noise ratios also did not strongly impair localization ability in open loop trials, but females exhibited reduced phonotaxis performance consistent with impaired localization during closed loop trials. We discuss these results in light of previous work on spatial hearing in anurans. PMID:24504182

  9. Recent progress in the assembly of nanodevices and van der Waals heterostructures by deterministic placement of 2D materials.

    PubMed

    Frisenda, Riccardo; Navarro-Moratalla, Efrén; Gant, Patricia; Pérez De Lara, David; Jarillo-Herrero, Pablo; Gorbachev, Roman V; Castellanos-Gomez, Andres

    2018-01-02

    Designer heterostructures can now be assembled layer-by-layer with unmatched precision thanks to the recently developed deterministic placement methods to transfer two-dimensional (2D) materials. This possibility constitutes the birth of a very active research field on the so-called van der Waals heterostructures. Moreover, these deterministic placement methods also open the door to fabricate complex devices, which would be otherwise very difficult to achieve by conventional bottom-up nanofabrication approaches, and to fabricate fully-encapsulated devices with exquisite electronic properties. The integration of 2D materials with existing technologies such as photonic and superconducting waveguides and fiber optics is another exciting possibility. Here, we review the state-of-the-art of the deterministic placement methods, describing and comparing the different alternative methods available in the literature, and we illustrate their potential to fabricate van der Waals heterostructures, to integrate 2D materials into complex devices and to fabricate artificial bilayer structures where the layers present a user-defined rotational twisting angle.

  10. Stent conformity in curved vascular models with simulated aneurysm necks using flat-panel CT: an in vitro study.

    PubMed

    Ebrahimi, N; Claus, B; Lee, C-Y; Biondi, A; Benndorf, G

    2007-05-01

    Radiographic visibility of self-expandable intracranial stents is insufficient for assessment of conformability and deployment characteristics. The purpose of this study was to evaluate stent mechanics in a curved vessel model by using Flat-Panel CT (FPCT). The following stents were used: Neuroform 2, Neuroform Treo, Enterprise, and LEO. All stents were bent in the same polytetrafluoroethylene tubes with various angles ranging from 150 degrees to 30 degrees . To visualize potential prolapse of the stent struts, 4-, 5-, and 8-mm openings were created. FPCTs were obtained using a C-arm with flat detector. FPCT scans provided excellent visualization of deployment characteristics and stent mechanics and was superior to digital subtraction angiography (DSA) and digital radiography (DR). The Neuroform2/Treo showed, with increasing angle and diameter of the opening, a continuous increase in cell size. These stents also showed an outward prolapse at the convexity and an inwards prolapse of struts at the concavity of the curvature. The Enterprise showed an increasing trend to flatten and to kink with curvatures that are more acute. The LEO showed fewer trends to kink but an inward crimping of its ends with more acute angles. Deployment characteristics and conformability to a curved vessel model vary considerably, depending on the angle and the stent design. Adverse mechanics such as increased cell opening, strut prolapse, flattening, and kinking occur during stent placement in a curved vessel model, and may gain clinical importance. FPCT is superior to DSA and DR in visualizing small metallic stents and enables accurate detection of adverse stent mechanics.

  11. [Characteristics in treatment of the hip in patients with Down syndrome].

    PubMed

    Peterlein, C-D; Schiel, M; Timmesfeld, N; Schofer, M D; Eberhardt, O; Wirth, T; Fernandez, F F

    2013-12-01

    The treatment of hip instability in patients with Down syndrome is challenging. We have performed different pelvic osteotomies and corrections at the proximal femur for this indication. This retrospective study was conducted to evaluate the clinical and radiological outcome of each intervention. All in all, 166 patients with Down syndrome were treated at our orthopaedic department in the observation period. Problems related to the hip joint were diagnosed in 63 of those patients. Only patients who underwent surgery were included in this study. The charts and X-rays of these 31 patients were evaluated with respect to the following parameters: incidence of the hip problem, concomitant diseases, temporal progress, kind of operation method and date, duration of stay in the hospital, after-care, follow-on surgery related to complications, AC angle, CE angle, ACM angle, CCD angle, index of migration according to Reimers, classification of Bauer and Kerschbauer and general morphology of the femoral head. The group was compared with an age-matched group of 21 patients with hip dysplasia. Those patients underwent the same sort of operation in the same year. In the Morbus Down group, we performed surgery for preservation of the hip in 49 cases. This included 13 osteotomies according to Chiari, 11 triple osteotomies according to Tönnis, 10 corrections by femoral varus derotation osteotomy, 8 pelvic osteotomies according to Pemberton, 5 pelvic osteotomies according to Salter and 2 open reductions of the hip. With respect to the moment of surgery, we detected three peaks of age. There was no difference in course of disease and quantity of complications between the groups. Satisfactory results concerning clinical and radiological outcome were achieved predominantly by complete redirectional acetabular osteotomies. Half of the patients who were solely treated by femoral varus derotation osteotomy needed follow-on surgery in the form of pelvic osteotomy. Comparison of preoperative and postoperative range of motion of the hip joint between groups detected capsular insufficiency, increased ligamentous laxity and muscular hypotonia in patients with Down syndrome. Comparison of pelvic radiographs demonstrated significant improvement concerning measured angles in both groups. Preoperative values with respect to AC angle and CE angle were demonstrated to be lower in the hip dysplasia group (p < 0.01); whereas values for ACM angle were comparable between groups. Hypermobility and secondary dislocation of the hip joint is a common problem in patients with Down syndrome, which often requires surgical intervention at an early stage. According to our data and clinical results we suggest a complete redirectional acetabular osteotomy in combination with capsular plication for treatment of this challenging condition. Georg Thieme Verlag KG Stuttgart · New York.

  12. Acoustic attraction, repulsion and radiation force cancellation on a pair of rigid particles with arbitrary cross-sections in 2D: Circular cylinders example

    NASA Astrophysics Data System (ADS)

    Mitri, F. G.

    2017-11-01

    The acoustic radiation forces arising on a pair of sound impenetrable cylindrical particles of arbitrary cross-sections are derived. Plane progressive, standing or quasi-standing waves with an arbitrary incidence angle are considered. Multiple scattering effects are described using the multipole expansion formalism and the addition theorem of cylindrical wave functions. An effective incident acoustic field on a particular object is determined, and used with the scattered field to derive closed-form analytical expressions for the radiation force vector components. The mathematical expressions for the radiation force components are exact, and have been formulated in partial-wave series expansions in cylindrical coordinates involving the angle of incidence, the reflection coefficient forming the progressive or the (quasi)standing wave field, the addition theorem, and the expansion coefficients. Numerical examples illustrate the analysis for two rigid circular cross-sections immersed in a non-viscous fluid. Computations for the dimensionless radiation force functions are performed with emphasis on varying the angle of incidence, the interparticle distance, the sizes of the particles as well as the characteristics of the incident field. Depending on the interparticle distance and angle of incidence, one of the particles yields neutrality; it experiences no force and becomes unresponsive (i.e., ;invisible;) to the linear momentum transfer of the effective incident field due to multiple scattering cancellation effects. Moreover, attractive or repulsive forces between the two particles may arise depending on the interparticle distance, the angle of incidence and size parameters of the particles. This study provides a complete analytical method and computations for the axial and transverse radiation force components in multiple acoustic scattering encompassing the cases of plane progressive, standing or quasi-standing waves of arbitrary incidence by a pair of scatterers. Potential applications concern the prediction of the forces used in acoustically-engineered metamaterials with reconfigurable periodicities, cloaking devices, and liquid crystals to name a few examples.

  13. Comparative proteomic study in serum of patients with primary open-angle glaucoma and pseudoexfoliation glaucoma.

    PubMed

    González-Iglesias, Héctor; Álvarez, Lydia; García, Montserrat; Escribano, Julio; Rodríguez-Calvo, Pedro Pablo; Fernández-Vega, Luis; Coca-Prados, Miguel

    2014-02-26

    Alterations in the sera proteins between patients with Primary Open-Angle Glaucoma (POAG), Pseudoexfoliation Glaucoma (PEXG), and healthy controls were identified through a proven approach utilizing equalization of high-abundance serum proteins with ProteoMiner™, two-dimensional fluorescent difference gel electrophoresis (2D-DIGE), MALDI-TOF/TOF, and nanoLC-MS-MS. Quantitative immunoassays of the 17 most-differentially-altered proteins identified in this analysis confirmed that they were also over expressed in the intact serum of newly recruited glaucoma patients. Overall, this report identifies a panel of candidates for glaucoma biomarkers and supports their further validation in large population studies. Additionally, functional pathway analysis of these candidate proteins suggested that they are part of a network linked to regulating immune and inflammatory-related processes. The data have been deposited to the ProteomeXchange with identifier PXD000198. POAG and PEXG are major causes of age-related blindness in the world; however, treatment can be very effective if they are identified early on in the progression. Genetic linkage studies can only explain a limited number of cases, suggesting that these forms of glaucoma are multigenic in nature. Other important factors, such as modifier genes, epigenetic influences, environmental and dietary agents, and inflammatory and oxidative effects are also believed to affect the development of these diseases. The characterization of metabolic and/or proteins changes, for example in bodily fluids, before the clinical manifestation of glaucoma is of considerable relevance for its early diagnosis. In the present work, identification of over-expressed proteins in serum of glaucoma patients (POAG and PEXG) linked to immune and inflammatory processes supports the finding that changes in these pathways also manifest systemically in patients with these pathologies. This study provides a new basis to validate the identified proteins as biomarkers of glaucoma in a large-scale-multiplexed screening in sera. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Shotgun proteomics reveals specific modulated protein patterns in tears of patients with primary open angle glaucoma naïve to therapy.

    PubMed

    Pieragostino, Damiana; Agnifili, Luca; Fasanella, Vincenzo; D'Aguanno, Simona; Mastropasqua, Rodolfo; Di Ilio, Carmine; Sacchetta, Paolo; Urbani, Andrea; Del Boccio, Piero

    2013-06-01

    Primary open angle glaucoma (POAG) is one of the main causes of irreversible blindness worldwide. The pathogenesis of POAG is still unclear. Alteration and sclerosis of trabecular meshwork with changes in aqueous humor molecular composition seem to play the key role. Increased intraocular pressure is widely known to be the main risk factor for the onset and progression of the disease. Unfortunately, the early diagnosis of POAG still remains the main challenge. In order to provide insight into the patho-physiology of glaucoma, here we report a shotgun proteomics approach to tears of patients with POAG naïve to therapy. Our proteomics results showed 27 differential tear proteins in POAG vs. CTRL comparison (25 up regulated proteins in the POAG group and two unique proteins in the CTRL group), 16 of which were associated with inflammatory response, free radical scavenging, cell-to-cell signaling and interaction. Overall the protein modulation shown in POAG tears proves the involvement of biochemical networks linked to inflammation. Among all regulated proteins, a sub-group of 12 up-regulated proteins in naïve POAG patients were found to be down-regulated in medically controlled POAG patients treated with prostanoid analogues (PGA), as reported in our previous work (i.e., lipocalin-1, lysozyme C, lactotransferrin, proline-rich-protein 4, prolactin-inducible protein, zinc-alpha-2-glycoprotein, polymeric immunoglobulin receptor, cystatin S, Ig kappa chain C region, Ig alpha-2 chain C region, immunoglobulin J chain, Ig alpha-1 chain C region). In summary, our findings indicate that the POAG tears protein expression is a mixture of increased inflammatory proteins that could be potential biomarkers of the disease, and their regulation may be involved in the mechanism by which PGA are able to decrease the intraocular pressure in glaucoma patients.

  15. Differential Protein Expression Profiles in Glaucomatous Trabecular Meshwork: An Evaluation Study on a Small Primary Open Angle Glaucoma Population.

    PubMed

    Micera, Alessandra; Quaranta, Luciano; Esposito, Graziana; Floriani, Irene; Pocobelli, Augusto; Saccà, Sergio Claudio; Riva, Ivano; Manni, Gianluca; Oddone, Francesco

    2016-02-01

    Primary open angle glaucoma (POAG) is a progressive optic neuropathy characterized by impaired aqueous outflow and extensive remodeling in the trabecular meshwork (TM). The aim of this study was to characterize and compare the expression patterns of selected proteins belonging to the tissue remodeling, inflammation and growth factor pathways in ex vivo glaucomatous and post-mortem TMs using protein-array analysis. TM specimens were collected from 63 white subjects, including 40 patients with glaucoma and 23 controls. Forty POAG TMs were collected at the time of surgery and 23 post-mortem specimens were from non-glaucomatous donor sclerocorneal tissues. Protein profiles were evaluated using a chip-based array consisting of 60 literature-selected antibodies. A different expression of some factors was observed in POAG TMs with respect to post-mortem specimens, either in abundance (interleukin [IL]10, IL6, IL5, IL7, IL12, IL3, macrophage inflammatory protein [MIP]1δ/α, vascular endothelial growth factor [VEGF], transforming growth factor beta 1 [TGFβ1], soluble tumor necrosis factor receptor I [sTNFRI]) or in scarcity (IL16, IL18, intercellular adhesion molecule 3 [ICAM3], matrix metalloproteinase-7 [MMP7], tissue inhibitor of metalloproteinase 1 [TIMP1]). MMP2, MMP7, TGFβ1, and VEGF expressions were confirmed by Western blot, zymography, and polymerase chain reaction. No difference in protein profile expression was detected between glaucomatous subtypes. The analysis of this small TM population highlighted some proteins linked to POAG, some previously reported and others of new detection (IL7, MIPs, sTNFαRI). A larger POAG population is required to select promising disease-associated biomarker candidates. This study was partially supported by the Fondazione Roma, the Italian Ministry of Health and the "National 5xMille 2010 tax donation to IRCCS-G.B. Bietti Foundation".

  16. Changes in the retrobulbar hemodynamic parameters after decreasing the elevated intraocular pressure in primary open-angle glaucoma patients.

    PubMed

    Marjanović, Ivan; Martinez, Antonio; Marjanović, Marija; Milić, Natasa; Kontić, Djordje; Hentova-Senćanić, Paraskeva; Marković, Vujica; Bozić, Marija

    2014-01-01

    Ocular blood flow (OBF) disturbances could be involved both in the pathogenesis and in progression of glaucomatous damage. The aim of the study was to compare the retrobulbar hemodynamic parameters in the ophthalmic artery (OA), central retinal artery (CRA) and short posterior cilliary arteries (SPCA) after decreasing the elevated intraocular pressure (IOP) in primary open-angle glaucoma (POAG) patients by using color Doppler imaging (CDI). We examined 60 patients (21 male and 39 female) with diagnosed and treated POAG. Thirty-nine patients had increased IOP (> 25 mm Hg). Peak-systolic velocity (PSV), end-diastolic velocity (EDV), Pourcelot resistance index (RI), and pulsatility index (PI) were assessed in the OA, CRA, and SPCA. IOP was measured both with the Goldmann Applanation tonometer (GAT) and with the Dynamic Contour tonometer (DCT), three times respectively. Ocular pulse amplitude (OPA) was measured using DCT. The retrobulbar parameters between the baseline and after IOP reduction showed no difference in measurements. After Bonferroni correction (p < or = 0.0056, alpha/9) statistical significance was recorded only in the following retrobulbar hemodynamic parameters; DCT (29.8 +/- 6.2 vs. 15.5 +/- 5.0), GAT (33.8 +/- 9.0 vs. 15.0 +/- 6.6) and OPA measurements (4.3 +/- 1.0 vs. 3.0 +/- 1.6), as compared to the baseline. There was no correlation between the changes in IOP measured with either DCT or GAT and changes in the hemodynamic parameters (p > 0.05 for all). Pearson correlation coefficient (95% CI) showed very good correlation for IOP measurements between DCT and GAT: at baseline 0.83 (0.71 to 0.90) and at the end 0.71 (0.55 to 0.83); p < 0.0001 for both measurements, but without any difference between them (p > 0.05). There was a lack of correlation between the changes in IOP measured with either DCT or GAT and the changes in the hemodynamic parameters.

  17. Open Data in Biomedical Science: Policy Drivers and Recent ...

    EPA Pesticide Factsheets

    EPA's progress in implementing the open data initiatives first outlined in the 2009 Presidential memorandum on open government and more specifically regarding publications and data from publications in the 2013 Holdren memorandum. The presentation outlines the major points in both memorandums regarding open data, presents several (but not exhaustive) EPA initiatives on open data, some of which occurred will before both policy memorandums. The presentation concludes by outlining the initiatives to ensure public access to all EPA publications through PubMed Central and all publication-associated data through the Environmental Data Gateway and Data.gov. The purpose of this presentation is to present EPA's progress in implementing the open data initiatives first outlined in the 2009 Presidential memorandum on open government and more specifically regarding publications and data from publications in the 2013 Holdren memorandum.

  18. Clinical and biomechanical changes following a 4-month toe-out gait modification program for people with medial knee osteoarthritis: a randomized controlled trial.

    PubMed

    Hunt, M A; Charlton, J M; Krowchuk, N M; Tse, C T F; Hatfield, G L

    2018-04-27

    To compare changes in knee pain, function, and loading following a 4-month progressive walking program with or without toe-out gait modification in people with medial tibiofemoral knee osteoarthritis. Individuals with medial knee osteoarthritis were randomized to a 4-month program to increase walking activity with (toe-out) or without (progressive walking) concomitant toe-out gait modification. The walking program was similar between the two groups, except that the gait modification group was trained to walk with 15° more toe-out. Primary outcomes included: knee joint pain (WOMAC), foot progression angles and knee joint loading during gait (knee adduction moment (KAM)). Secondary outcomes included WOMAC function, timed stair climb, and knee flexion moments during gait. Seventy-nine participants (40 in toe-out group, 39 in progressive walking group) were recruited. Intention-to-treat analysis showed no between-group differences in knee pain, function, or timed stair climb. However, the toe-out group exhibited significantly greater changes in foot progression angle (mean difference = -9.04° (indicating more toe-out), 95% CI: -11.22°, -6.86°; P < 0.001), late stance KAM (mean difference = -0.26 %BW*ht, 95% CI: -0.39 %BW*ht, -0.12 %BW*ht, P < 0.001) and KAM impulse (-0.06 %BW*ht*s, 95% CI: -0.11 %BW*ht*s, -0.01 %BW*ht*s; P = 0.031) compared to the progressive walking group at follow-up. The only between-group difference that remained at a 1-month retention assessment was foot progression angle, with greater changes in the toe-out group (mean difference = -6.78°, 95% CI: -8.82°, -4.75°; P < 0.001). Though both groups experienced improvements in self-reported pain and function, only the toe-out group experienced biomechanical improvements. NCT02019108. Copyright © 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  19. Analysis of Balance Ability Dependent on the Angle of the Knee Joint in Females in Their 20s

    PubMed Central

    Yoon, Se-Won; Lee, Jeong-Woo; Cho, Woon-Su; Kim, An-Na; Lee, Kyung-Hee

    2013-01-01

    The aim of this study was to investigate how balance ability according to angle of the knee joint changes in young female adults wearing a knee orthosis. [Methods] This study was conducted with 11 healthy female adults. The subjects used a knee brace that could be set to angles of 0°, 15°, and 30° of knee flexion. The ability to balance was evaluated by balance assessment. A total of four postures were used for measurements: a forward-facing posture with the eyes open on a stable surface (NO), a forward-facing posture with the eyes closed on a stable surface (NC), a forward-facing posture with the eyes open on an unstable surface (PO), and a forward-facing posture with the eyes closed on an unstable surface (PC). [Results] Regarding the weight distribution index and stability index on a stable surface, there was no interaction according to whether there was visual deprivation or not or according to knee flexion angle. Furthermore, the stability index on an unstable surface showed no interaction according to whether there was visual deprivation or not or according to knee flexion angle. But the WDI on a stable surface showed no interaction according to whether there was visual deprivation or not or according to knee flexion angle. [Conclusion] There were significant differences in the knee extension range of motion of normal elderly people and knee osteoarthritis, and the quadriceps femoris played an important role in knee function in individuals with knee osteoarthritis. PMID:24259902

  20. The effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle-closure glaucoma (EAGLE): study protocol for a randomized controlled trial.

    PubMed

    Azuara-Blanco, Augusto; Burr, Jennifer M; Cochran, Claire; Ramsay, Craig; Vale, Luke; Foster, Paul; Friedman, David; Quayyum, Zahidul; Lai, Jimmy; Nolan, Winnie; Aung, Tin; Chew, Paul; McPherson, Gladys; McDonald, Alison; Norrie, John

    2011-05-23

    Glaucoma is the leading cause of irreversible blindness. Although primary open-angle glaucoma is more common, primary angle-closure glaucoma (PACG) is more likely to result in irreversible blindness. By 2020, 5·3 million people worldwide will be blind because of PACG. The current standard care for PACG is a stepped approach of a combination of laser iridotomy surgery (to open the drainage angle) and medical treatment (to reduce intraocular pressure). If these treatments fail, glaucoma surgery (eg, trabeculectomy) is indicated. It has been proposed that, because the lens of the eye plays a major role in the mechanisms leading to PACG, early clear lens extraction will improve glaucoma control by opening the drainage angle. This procedure might reduce the need for drugs and glaucoma surgery, maintain good visual acuity, and improve quality of life compared with standard care.EAGLE aims to evaluate whether early lens extraction improves patient-reported, clinical outcomes, and cost-effectiveness, compared with standard care. EAGLE is a multicentre pragmatic randomized trial. All people presenting to the recruitment centres in the UK and east Asia with newly diagnosed PACG and who are at least 50 years old are eligible.The primary outcomes are EQ-5D, intraocular pressure, and incremental cost per quality adjusted life year (QALY) gained. Other outcomes are: vision and glaucoma-specific patient-reported outcomes, visual acuity, visual field, angle closure, number of medications, additional surgery (e.g., trabeculectomy), costs to the health services and patients, and adverse events.A single main analysis will be done at the end of the trial, after three years of follow-up. The analysis will be based on all participants as randomized (intention to treat). 400 participants (200 in each group) will be recruited, to have 90% power at 5% significance level to detect a difference in EQ-5D score between the two groups of 0·05, and a mean difference in intraocular pressure of 1·75 mm Hg. The study will have 80% power to detect a difference of 15% in the glaucoma surgery rate. ISRCTN44464607.

  1. Progress Towards an Open Data Ecosystem for Australian Geochemistry and Geochronology Data

    NASA Astrophysics Data System (ADS)

    McInnes, B.; Rawling, T.; Brown, W.; Liffers, M.; Wyborn, L. A.; Brown, A.; Cox, S. J. D.

    2016-12-01

    Technological improvements in laboratory automation and microanalytical methods are producing an unprecedented volume of high-value geochemical data for use by geoscientists in understanding geological and planetary processes. In contrast, the research infrastructure necessary to systematically manage, deliver and archive analytical data has not progressed much beyond the minimum effort necessary to produce a peer-reviewed publication. Anecdotal evidence indicates that the majority of publically funded data is underreported, and what is published is relatively undiscoverable to experienced researchers let alone the general public. Government-funded "open data" initiatives have a role to play in the development of networks of data management and delivery ecosystems and practices allowing access to publically funded data. This paper reports on progress in Australia towards creation of an open data ecosystem involving multiple academic and government research institutions cooperating to create an open data architecture linking researchers, physical samples, sample metadata, laboratory metadata, analytical data and consumers.

  2. Progression of Local Glaucomatous Damage Near Fixation as Seen with Adaptive Optics Imaging.

    PubMed

    Hood, Donald C; Lee, Dongwon; Jarukasetphon, Ravivarn; Nunez, Jason; Mavrommatis, Maria A; Rosen, Richard B; Ritch, Robert; Dubra, Alfredo; Chui, Toco Y P

    2017-07-01

    Deep glaucomatous defects near fixation were followed over time with an adaptive optics-scanning light ophthalmoscope (AO-SLO) to better understand the progression of these defects and to explore the use of AO-SLO in detecting them. Six eyes of 5 patients were imaged with an AO-SLO from 2 to 4 times for a range of 14.6 to 33.6 months. All eyes had open-angle glaucoma with deep defects in the superior visual field (VF) near fixation as defined by 10-2 VFs with 5 or more points less than -15 dB; two of the eyes had deep defects in the inferior VF as well. AO-SLO images were obtained around the temporal edge of the disc. In 4 of the 6 eyes, the edge of the inferior-temporal disc region of the retinal nerve fiber (RNF) defect seen on AO-SLO moved closer to fixation within 10.6 to 14.7 months. In 4 eyes, RNF bundles in the affected region appeared to lose contrast and/or disappear. Progressive changes in RNF bundles associated with deep defects on 10-2 VFs can be seen within about 1 year with AO-SLO imaging. These changes are well below the spatial resolution of the 10-2 VF. On the other hand, subtle thinning of regions with RNF bundles is not easy to see with current AO-SLO technology, and may be better followed with OCT. AO-SLO imaging may be useful in clinical trials designed to see very small changes in deep defects.

  3. Evaluation of anterior chamber angle under dark and light conditions in angle closure glaucoma: An anterior segment OCT study.

    PubMed

    Masoodi, Habibeh; Jafarzadehpur, Ebrahim; Esmaeili, Alireza; Abolbashari, Fereshteh; Ahmadi Hosseini, Seyed Mahdi

    2014-08-01

    To evaluate changes of nasal and temporal anterior chamber angle (ACA) in subjects with angle closure glaucoma using Spectralis AS-OCT (SAS-OCT) under dark and light conditions. Based on dark-room gonioscopy, 24 subjects with open angles and 86 with narrow angles participated in this study. The nasal and temporal angle opening distance at 500 μm anterior to the scleral spur (AOD500), nasal and temporal ACA were measured using SAS-OCT in light and dark conditions. In 2 groups, ACA and AOD500 in nasal and temporal quadrants were significantly greater in light compared to dark (all with p=0.000). The AOD500 and ACA were significantly higher in nasal than temporal in measured conditions for 2 groups except the ACA and AOD500 of normal group measured in light. The difference between nasal and temporal in dark (29.07 ± 65.71 μm for AOD500 and 5.7 ± 4.07° for ACA) was greater than light (24.86 ± 79.85 μm for AOD500 and 2.09 ± 7.21° for ACA) condition. But the difference was only significant for ACA (p=0.000). The correlation analysis showed a negative correlation between AOD500 and pupil diameter in temporal and nasal quadrants (both with p=0.000). While temporal AOD500 difference correlated with spherical equivalent, temporal and asal gonioscopy, nasal AOD correlated with IOP, temporal and nasal gonioscopy. Clinically important changes in ACA structure could be detected with SAS-OCT in nasal and temporal quadrants under different illumination intensity. The results could help in improvement of examination condition for better and more accurate assessment of individuals with angle closure glaucoma. Copyright © 2014 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  4. Electrons with E greater than 40 MeV in the earth's radiation belt

    NASA Astrophysics Data System (ADS)

    Galper, A. M.; Grachev, V. M.; Dmitrenko, V. V.; Kirillov-Ugriumov, V. G.; Polukhina, N. G.; Ulin, S. E.

    1983-10-01

    The spatial-angle characteristics of radiation-belt electrons with energies exceeding 40 MeV have been constructed on the basis of data from the Elena-F instrument on the Salyut 6-Soyuz-Progress complex. A sufficiently narrow pitch-angle distribution is found, which indicates that high-energy electrons observed in the region of the Brazilian magnetic anomaly are trapped by the geomagnetic field.

  5. A young Botswana patient with congenital iris ectropion uvea.

    PubMed

    Shifa, Jemal Zeberga; Nkomazana, Othokawa; Bekele, Negussie Alula; Kassa, Mamo Woldu

    2016-01-01

    Congenital iris ectropion is a rare condition; non-progressive anomaly characterised by the presence of iris pigment epithelium on the anterior surface of the iris stroma and is frequently associated with anterior iris insertion, dysgenesis of the drainage angle and glaucoma. This paper describes unusual case of bilateral case of congenital iris ectropion in adult patient with pupillary abnormality, normal anterior chamber angle structure and with no evidence of glaucoma.

  6. MO-F-CAMPUS-T-01: Radiosurgery of Multiple Brain Metastases with Single-Isocenter VMAT: Optimizing Treatment Geometry to Reduce Normal Brain Dose

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu, Q; Snyder, K; Liu, C

    Purpose: To develop an optimization algorithm to reduce normal brain dose by optimizing couch and collimator angles for single isocenter multiple targets treatment of stereotactic radiosurgery. Methods: Three metastatic brain lesions were retrospectively planned using single-isocenter volumetric modulated arc therapy (VMAT). Three matrices were developed to calculate the projection of each lesion on Beam’s Eye View (BEV) by the rotating couch, collimator and gantry respectively. The island blocking problem was addressed by computing the total area of open space between any two lesions with shared MLC leaf pairs. The couch and collimator angles resulting in the smallest open areas weremore » the optimized angles for each treatment arc. Two treatment plans with and without couch and collimator angle optimization were developed using the same objective functions and to achieve 99% of each target volume receiving full prescription dose of 18Gy. Plan quality was evaluated by calculating each target’s Conformity Index (CI), Gradient Index (GI), and Homogeneity index (HI), and absolute volume of normal brain V8Gy, V10Gy, V12Gy, and V14Gy. Results: Using the new couch/collimator optimization strategy, dose to normal brain tissue was reduced substantially. V8, V10, V12, and V14 decreased by 2.3%, 3.6%, 3.5%, and 6%, respectively. There were no significant differences in the conformity index, gradient index, and homogeneity index between two treatment plans with and without the new optimization algorithm. Conclusion: We have developed a solution to the island blocking problem in delivering radiation to multiple brain metastases with shared isocenter. Significant reduction in dose to normal brain was achieved by using optimal couch and collimator angles that minimize total area of open space between any of the two lesions with shared MLC leaf pairs. This technique has been integrated into Eclipse treatment system using scripting API.« less

  7. The influence of third molars in the line of mandibular angle fractures on wound and bone healing.

    PubMed

    Ulbrich, N; Ettl, T; Waiss, W; Gosau, M; Moralis, A; Reichert, T E; Mueller, S

    2016-07-01

    The objective of this study was to evaluate postoperative complications after removal or retention of the third molar in the line of mandibular angle fractures. This retrospective study included the data of 98 patients with a molar in the line of a mandibular angle fracture treated with internal reduction and mini-plate fixation at our department over 9 years. Patients were classified into two groups: tooth removal during osteosynthesis (n = 45) and tooth retention (n = 55). The primary target criterion was the incidence of minor (outpatient treatment, local measures) and major (surgical revision, rehospitalisation) complications. Time between trauma and surgery was 1.4 days (range 0 to 12), and the average follow-up 291 days (range 66 to 863). Regarding the eruption status, 26 of 52 (50.0 %) impacted third molars, 11 of 19 (57.9 %) incompletely erupted and 8 of 27 (29.6 %) completely erupted molars had been removed during open reduction. Overall, 17 (17.3 %) patients had postoperative minor (n = 7) or major (n = 10) complications, in detail 10/45 (22.0 %) patients after tooth removal and 7/55 (13 %) patients after tooth retention (p = 0.286). Complication rates between impacted and incompletely erupted third molars (impacted molars 15.0 %, incompletely erupted molars 10.0 %) did not differ significantly, but completely erupted molars had a complication rate of 26.0 %. Mandibular angle fractures with a completely erupted third molar show the highest complication rate after open reduction and osteosynthesis. Retention of a non-infectious third molar facilitates open reduction and does not increase the complication risk. The study helps with the decision of removing or retention of a third molar during surgical treatment of a mandibular angle fracture.

  8. Evaluation and comparison of indentation ultrasound biomicroscopy gonioscopy in relative pupillary block, peripheral anterior synechia, and plateau iris configuration.

    PubMed

    Matsunaga, Koichi; Ito, Kunio; Esaki, Koji; Sugimoto, Kota; Sano, Toru; Miura, Katsuya; Sasoh, Mikio; Uji, Yukitaka

    2004-12-01

    To evaluate and compare the findings and changes of the anterior chamber angle configuration with indentation ultrasound biomicroscopy (UBM) gonioscopy in relative pupillary block (RPB), peripheral anterior synechia (PAS), and plateau iris configuration (PIC). This study included 73 eyes of 52 patients with RPB (n = 26), PAS (n = 21), or PIC (n = 26). First, a conventional UBM scan was performed using a normal size standard eye cup before indentation. Then, for indentation UBM gonioscopy, scans were performed using a new eye cup that we designed. For evaluation of the angle, angle opening distance 500 and angle recess area were recorded and evaluated with regard to the effect of expansion on the anterior chamber angle. Indentation UBM gonioscopy showed the characteristic images in each of the eyes. The angle of all examined eyes was significantly widened with indentation (P < 0.01). The angle changes in eyes with RPB were significantly greater than in eyes with PAS or PIC (P < 0.01). Indentation UBM gonioscopy is a very useful method for observing the angle and diagnosis of RPB, PAS, and PIC.

  9. Conformational states and recognition of amyloidogenic peptides of human insulin-degrading enzyme.

    PubMed

    McCord, Lauren A; Liang, Wenguang G; Dowdell, Evan; Kalas, Vasilios; Hoey, Robert J; Koide, Akiko; Koide, Shohei; Tang, Wei-Jen

    2013-08-20

    Insulin-degrading enzyme (IDE) selectively degrades the monomer of amyloidogenic peptides and contributes to clearance of amyloid β (Aβ). Thus, IDE retards the progression of Alzheimer's disease. IDE possesses an enclosed catalytic chamber that engulfs and degrades its peptide substrates; however, the molecular mechanism of IDE function, including substrate access to the chamber and recognition, remains elusive. Here, we captured a unique IDE conformation by using a synthetic antibody fragment as a crystallization chaperone. An unexpected displacement of a door subdomain creates an ~18-Å opening to the chamber. This swinging-door mechanism permits the entry of short peptides into the catalytic chamber and disrupts the catalytic site within IDE door subdomain. Given the propensity of amyloidogenic peptides to convert into β-strands for their polymerization into amyloid fibrils, they also use such β-strands to stabilize the disrupted catalytic site resided at IDE door subdomain for their degradation by IDE. Thus, action of the swinging door allows IDE to recognize amyloidogenicity by substrate-induced stabilization of the IDE catalytic cleft. Small angle X-ray scattering (SAXS) analysis revealed that IDE exists as a mixture of closed and open states. These open states, which are distinct from the swinging door state, permit entry of larger substrates (e.g., Aβ, insulin) to the chamber and are preferred in solution. Mutational studies confirmed the critical roles of the door subdomain and hinge loop joining the N- and C-terminal halves of IDE for catalysis. Together, our data provide insights into the conformational changes of IDE that govern the selective destruction of amyloidogenic peptides.

  10. Influence of guide vane opening on the flow phenomena in a pump turbine during a fast transition from pump mode to generating mode

    NASA Astrophysics Data System (ADS)

    Stens, C.; Riedelbauch, S.

    2017-04-01

    Due to a more fluctuating energy production caused by renewable energies such as wind and solar power, the number of changes between operating points in pumped storage power plants has increased over the last years. To further increase available regulating power, it is desirable to speed up these changes of operation conditions in Hydro units. Previous studies showed that CFD is well capable of predicting the flow phenomena in the machine under unsteady conditions for a large guide vane opening angle. The present paper investigates the benefits of nearly closed guide vanes during the transition. Results are compared between the two different angles as well as between simulation and measurement.

  11. Nonimaging Optical Illumination System

    DOEpatents

    Winston, Roland

    1994-02-22

    A nonimaging illumination or concentration optical device. An optical device is provided having a light source, a light reflecting surface with an opening and positioned partially around the light source which is opposite the opening of the light reflecting surface. The light reflecting surface is disposed to produce a substantially uniform intensity output with the reflecting surface defined in terms of a radius vector R.sub.i in conjunction with an angle .phi..sub.i between R.sub.i, a direction from the source and an angle .theta..sub.i between direct forward illumination and the light ray reflected once from the reflecting surface. R.sub.i varies as the exponential of tan (.phi..sub.i -.theta..sub.i)/2 integrated over .phi..sub.i.

  12. Moving through MOOCs: Understanding the Progression of Users in Massive Open Online Courses

    ERIC Educational Resources Information Center

    Perna, Laura W.; Ruby, Alan; Boruch, Robert F.; Wang, Nicole; Scull, Janie; Ahmad, Seher; Evans, Chad

    2014-01-01

    This paper reports on the progress of users through 16 Coursera courses taught by University of Pennsylvania faculty for the first time between June 2012 and July 2013. Using descriptive analyses, this study advances knowledge by considering two definitions of massive open online course (MOOC) users (registrants and starters), comparing two…

  13. Effectiveness Using Circular Fibre Steel Flap Gate As a Control Structure Towards the Hydraulic Characteristics in Open Channel

    NASA Astrophysics Data System (ADS)

    Adib, M. R. M.; Amirza, A. R. M.; Wardah, T.; Junaidah, A.

    2016-07-01

    Hydraulic control gate structure plays an important role in regulating the flow of water in river, canal or water reservoir. One of the most appropriate structures in term of resolving the problem of flood occured is the construction of circular fibre steel flap gate. Therefore, an experiment has been conducted by using an open channel model at laboratory. In this case, hydraulic jump and backwater were the method to determined the hydraulic characteristics of circular fibre steel flap gate in an open channel model. From the experiment, the opening angle of flap gate can receive discharges with the highest flow rate of 0.035 m3/s with opening angle was 47°. The type of jump that occurs at the slope of 1/200 for a distance of 5.0 m is a standing jump or undulating wave. The height of the backwater can be identified based on the differences of specific force which is specific force before jump, F1 and specific force after jump, F2 from the formation of backwater. Based on the research conducted, the tendency of incident backwater wave occurred was high in every distance of water control location from water inlet is flap slope and the slope of 1/300 which is 0.84 m/s and 0.75 m/s of celerity in open channel model.

  14. Study of long term structural and functional changes in medically controlled glaucoma

    PubMed Central

    Pandey, Achyut N; Sujata, S

    2014-01-01

    AIM Prospectively analyze the long term structural and functional changes in patients of primary open angle glaucoma (POAG) receiving medical therapy (beta blockers and non beta blockers). In this study an attempt has been made to evaluate whether medical reduction of IOP prevents or delays the progression of glaucomatous visual field loss and/or optic nerve damage in patients with open angle glaucoma. METHODS Study conducted over a period of 27 months, at a tertiary eye care hospital including both eyes of 40 patients with POAG. Group 1 (20 patients, 40 eyes) received beta-blockers, and Group 2 (20 patients, 40 eyes) received non-beta-blockers. Each patient underwent intraocular pressure measurement, best corrected visual acuity, slit-lamp, fundus examination, gonioscopy, central corneal thickness, visual field assessment by Humphrey automated perimetry and retinal nerve fibre layer thickness by Stratus optical coherence tomography at baseline and at two subsequent visits. The average time interval between each visit was 10-11 months. The statistical analysis was done using one-way analysis of variance (ANOVA). Post-hoc test, using tukey' method were adopted. Probablity (P) value of 0.05 or less was considered to be statistically significant. RESULTS A total of 80 eyes of 40 patients of POAG were enrolled, 24 males, 16 females, age group 50-80 years. In both beta and non beta blocker group, reduction (improvement) in mean IOP from initial levels to the levels achieved at the 2nd and 3rd visits was statistically significant. One way ANOVA (df=2), fisher f value=11.64, P=0.000, one way ANOVA (df=3), fisher f value=35.61, P=0.000. Both mean deviation (MD) and pattern standard deviation (PSD) in both beta and non beta blockers at different visits were not statistically significant. Retinal nerve fibre layer thickness (RNFL) -only mean inferior retinal nerve fibre layer, the difference between the mean value in beta and non beta blocker groupwere statistically significant. [unpaired t test value (df=78) =2.27, P=0.03]. Side effects with beta blocker were conjunctival hyperemia (10%), burning (5%), and conjunctival hyperemia (5%) in non beta blockers. CONCLUSION Non-beta-blockers are as effective as beta-blockers in bringing about a significant lowering of intraocular pressure to the normal range, and in preventing progressive damage to the visual fields and retinal nerve fibre layer. The absence of systemic side effects and superior IOP lowering efficacy has made non beta-blockers attractive for first line therapy for the treatment of glaucoma worldwide. PMID:24634878

  15. Study of long term structural and functional changes in medically controlled glaucoma.

    PubMed

    Pandey, Achyut N; Sujata, S

    2014-01-01

    Prospectively analyze the long term structural and functional changes in patients of primary open angle glaucoma (POAG) receiving medical therapy (beta blockers and non beta blockers). In this study an attempt has been made to evaluate whether medical reduction of IOP prevents or delays the progression of glaucomatous visual field loss and/or optic nerve damage in patients with open angle glaucoma. Study conducted over a period of 27 months, at a tertiary eye care hospital including both eyes of 40 patients with POAG. Group 1 (20 patients, 40 eyes) received beta-blockers, and Group 2 (20 patients, 40 eyes) received non-beta-blockers. Each patient underwent intraocular pressure measurement, best corrected visual acuity, slit-lamp, fundus examination, gonioscopy, central corneal thickness, visual field assessment by Humphrey automated perimetry and retinal nerve fibre layer thickness by Stratus optical coherence tomography at baseline and at two subsequent visits. The average time interval between each visit was 10-11 months. The statistical analysis was done using one-way analysis of variance (ANOVA). Post-hoc test, using tukey' method were adopted. Probablity (P) value of 0.05 or less was considered to be statistically significant. A total of 80 eyes of 40 patients of POAG were enrolled, 24 males, 16 females, age group 50-80 years. In both beta and non beta blocker group, reduction (improvement) in mean IOP from initial levels to the levels achieved at the 2nd and 3rd visits was statistically significant. One way ANOVA (df=2), fisher f value=11.64, P=0.000, one way ANOVA (df=3), fisher f value=35.61, P=0.000. Both mean deviation (MD) and pattern standard deviation (PSD) in both beta and non beta blockers at different visits were not statistically significant. Retinal nerve fibre layer thickness (RNFL) -only mean inferior retinal nerve fibre layer, the difference between the mean value in beta and non beta blocker groupwere statistically significant. [unpaired t test value (df=78) =2.27, P=0.03]. Side effects with beta blocker were conjunctival hyperemia (10%), burning (5%), and conjunctival hyperemia (5%) in non beta blockers. Non-beta-blockers are as effective as beta-blockers in bringing about a significant lowering of intraocular pressure to the normal range, and in preventing progressive damage to the visual fields and retinal nerve fibre layer. The absence of systemic side effects and superior IOP lowering efficacy has made non beta-blockers attractive for first line therapy for the treatment of glaucoma worldwide.

  16. Objective evaluation of female feet and leg joint conformation at time of selection and post first parity in swine.

    PubMed

    Stock, J D; Calderón Díaz, J A; Rothschild, M F; Mote, B E; Stalder, K J

    2018-06-09

    Feet and legs of replacement females were objectively evaluated at selection, i.e. approximately 150 days of age (n=319) and post first parity, i.e. any time after weaning of first litter and before 2nd parturition (n=277) to 1) compare feet and leg joint angle ranges between selection and post first parity; 2) identify feet and leg joint angle differences between selection and first three weeks of second gestation; 3) identify feet and leg join angle differences between farms and gestation days during second gestation; and 4) obtain genetic variance components for conformation angles for the two time points measured. Angles for carpal joint (knee), metacarpophalangeal joint (front pastern), metatarsophalangeal joint (rear pastern), tarsal joint (hock), and rear stance were measured using image analysis software. Between selection and post first parity significant differences were observed for all joints measured (P < 0.05). Knee, front and rear pastern angles were less (more flexion), and hock angles were greater (less flexion) as age progressed (P < 0.05), while the rear stance pattern was less (feet further under center) at selection than post first parity (only including measures during first three weeks of second gestation). Only using post first parity leg conformation information, farm was a significant source of variation for front and rear pasterns and rear stance angle measurements (P < 0.05). Knee angle was less (more flexion) (P < 0.05) as gestation age progressed. Heritability estimates were low to moderate (0.04 - 0.35) for all traits measured across time points. Genetic correlations between the same joints at different time points were high (> 0.8) between the front leg joints and low (<0.2) between the rear leg joints. High genetic correlations between time points indicate that the trait can be considered the same at either time point, and low genetic correlations indicate that the trait at different time points should be considered as two separate traits. Minimal change in the front leg suggests conformation traits that remain between selection and post first parity, while larger changes in rear leg indicate that rear leg conformation traits should be evaluated at multiple time periods.

  17. Automated 3D ultrasound measurement of the angle of progression in labor.

    PubMed

    Montaguti, Elisa; Rizzo, Nicola; Pilu, Gianluigi; Youssef, Aly

    2018-01-01

    To assess the feasibility and reliability of an automated technique for the assessment of the angle of progression (AoP) in labor by using three-dimensional (3D) ultrasound. AoP was assessed by using 3D transperineal ultrasound by two operators in 52 women in active labor to evaluate intra- and interobserver reproducibility. Furthermore, intermethod agreement between automated and manual techniques on 3D images, and between automated technique on 3D vs 2D images were evaluated. Automated measurements were feasible in all cases. Automated measurements were considered acceptable in 141 (90.4%) out of the 156 on the first assessments and in all 156 after repeating measurements for unacceptable evaluations. The automated technique on 3D images demonstrated good intra- and interobserver reproducibility. The 3D-automated technique showed a very good agreement with the 3D manual technique. Notably, AoP calculated with the 3D automated technique were significantly wider in comparison with those measured manually on 3D images (133 ± 17° vs 118 ± 21°, p = 0.013). The assessment of the angle of progression through 3D ultrasound is highly reproducible. However, automated software leads to a systematic overestimation of AoP in comparison with the standard manual technique thus hindering its use in clinical practice in its present form.

  18. A study of progress of labour using intrapartum translabial ultrasound, assessing head station, direction, and angle of descent.

    PubMed

    Tutschek, B; Braun, T; Chantraine, F; Henrich, W

    2011-01-01

    Intrapartum translabial ultrasound (ITU) has the potential to objectively and quantitatively assess the progress of labour. The relationships between the different ITU parameters and their development during normal term labour have not been studied. Observational study. University teaching hospital. Labouring women with normal term fetuses in cephalic presentation. Intrapartum translabial ultrasound measurements for 'head station', 'head direction', and 'angle of descent' (AoD) were taken in 50 labouring women, compared, studied for repeatability, and correlated with the progress of labour. Reproducibility and correlation of ITU parameters and their pattern of changes during labour. All three ITU parameters were clinically well reproducible. AoD and head station were interchangeable, and could be calculated from each other. Head station and head direction changed in a typical pattern along the birth canal. Time to delivery correlated with ITU head station. Intrapartum translabial ultrasound is a simple technique that improves the understanding of normal and abnormal labour, enables the objective measurement of birth progress and provides a more scientific basis for assessing labour. © 2010 The Authors Journal compilation © RCOG 2010 BJOG An International Journal of Obstetrics and Gynaecology.

  19. Effects of wind velocity and slope on flame properties

    Treesearch

    David R. Weise; Gregory S. Biging

    1996-01-01

    Abstract: The combined effects of wind velocity and percent slope on flame length and angle were measured in an open-topped, tilting wind tunnel by burning fuel beds composed of vertical birch sticks and aspen excelsior. Mean flame length ranged from 0.08 to 1.69 m; 0.25 m was the maximum observed flame length for most backing fires. Flame angle ranged from -46o to 50o...

  20. CONTINUOUS ROTATION SCATTERING CHAMBER

    DOEpatents

    Verba, J.W.; Hawrylak, R.A.

    1963-08-01

    An evacuated scattering chamber for use in observing nuclear reaction products produced therein over a wide range of scattering angles from an incoming horizontal beam that bombards a target in the chamber is described. A helically moving member that couples the chamber to a detector permits a rapid and broad change of observation angles without breaching the vacuum in the chamber. Also, small inlet and outlet openings are provided whose size remains substantially constant. (auth)

  1. Signature of non-isotropic distribution of stellar rotation inclination angles in the Praesepe cluster

    NASA Astrophysics Data System (ADS)

    Kovacs, Geza

    2018-04-01

    The distribution of the stellar rotation axes of 113 main sequence stars in the open cluster Praesepe are examined by using current photometric rotation periods, spectroscopic rotation velocities, and estimated stellar radii. Three different samples of stellar rotation data on spotted stars from the Galactic field and two independent samples of planetary hosts are used as control samples to support the consistency of the analysis. Considering the high completeness of the Praesepe sample and the behavior of the control samples, we find that the main sequence F - K stars in this cluster are susceptible to rotational axis alignment. Using a cone model, the most likely inclination angle is 76° ± 14° with a half opening angle of 47° ± 24°. Non-isotropic distribution of the inclination angles is preferred over the isotropic distribution, except if the rotation velocities used in this work are systematically overestimated. We found no indication of this being the case on the basis of the currently available data. Data are only available at the CDS, together with the other two compiled datasets used in this paper, via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/612/L2

  2. Bone morphotypes of the varus and valgus knee.

    PubMed

    Thienpont, E; Schwab, P E; Cornu, O; Bellemans, J; Victor, J

    2017-03-01

    Coronal deformity correction with total knee arthroplasty (TKA) is an important feature in the treatment of osteoarthritis (OA). The hypothesis of this study was that bone morphology would be different in varus and valgus deformity, both before osteoarthritis development as well as during and after the disease process of OA. Retrospective study with measurements on preoperative and postoperative full leg standing radiographs of 96 patients who underwent TKA. The included patients were selected for this study because they had an OA knee on one side and a non-arthritic knee on the contralateral side presenting the same type of alignment as the to-be-operated knee (varus or valgus alignment on both sides). The control group of 46 subjects was a group of patients with neutral mechanical alignment who presented for ligamentous problems. A single observer measured mechanical alignment, anatomical alignment, anatomical-mechanical femoral angle and intra-articular bone morphology parameters with an accuracy of 1°. Varus OA group has less distal femoral valgus (mLDFA 89°) than control group (87°) and valgus OA group (mLDFA 85°). Varus OA group has same varus obliquity as control group (MPTA 87°) but more than valgus OA group (MPTA 90°). Joint Line Congruency Angle (JLCA) is 3°open on lateral side in varus and medially open in valgus OA group (2°). The non-arthritic valgus group presents a constitutional mechanical valgus of 184° Hip-Knee-Ankle (HKA) angle. Varus deformity in OA as measured with an HKA angle (HKA) <177° is a combination of distal femoral wear, tibial varus obliquity and lateral joint line opening. Valgus deformity in OA with an HKA > 183° is a combination of femoral distal joint line obliquity and wear combined with medial opening due to medial collateral ligament stretching. The clinical importance of bone morphotype analysis is that it shows the intra-articular potential of alignment correction when mechanical axis cuts are performed. Bone morphology in varus and valgus deformity is different before and after osteoarthritis. Perpendicular cuts to mechanical axes do not necessarily lead to neutral mechanical axis. Constitutional mechanical valgus was observed as 184° HKA angle before the development of OA. Level IV study.

  3. Relationship Between Anterior Lamina Cribrosa Surface Tilt and Glaucoma Development in Myopic Eyes.

    PubMed

    Lee, Eun Jung; Han, Jong Chul; Kee, Changwon

    2017-05-01

    To evaluate the anterior lamina cribrosa (LC) surface tilt angle in myopic eyes and associate it with glaucoma development. In this retrospective study, medical records of myopic patients referred for glaucoma examination from July 1, 2012 to March 30, 2016 were reviewed. Comprehensive ophthalmic examination including spectral-domain optical coherence tomography were performed. We measured the angle of anterior LC surface tilt against Bruch's membrane opening from optical coherence tomography images at the center of the clinical optic disc margin. In horizontal and vertical sections, the angles were defined as α and β, respectively. Patients were grouped according to the presence of glaucomatous damage and factors including optic nerve head morphologic parameters and LC tilt angles were compared between the 2 groups. Among 138 patients originally enrolled, 102 patients were finally analyzed. One eye from 1 patient was randomly chosen. Fifty-five eyes had glaucoma and 47 were normal. The degree of myopia and all optic nerve head morphologic parameters were not significantly different between the 2 groups. However, |α| and |β| were significantly larger in the glaucoma group (all P<0.001), and significances were maintained in multivariate analysis (P<0.001). Larger anterior LC surface tilt angles were related to the presence of glaucoma in normal-pressure myopic eyes. Angulation of the LC against Bruch's membrane opening plane might be associated with increased glaucoma susceptibility in myopic eyes. Further investigations are warranted before clinical utilization of LC tilt as glaucoma susceptibility biomarker.

  4. Open-field arena boundary is a primary object of exploration for Drosophila

    PubMed Central

    Soibam, Benjamin; Mann, Monica; Liu, Lingzhi; Tran, Jessica; Lobaina, Milena; Kang, Yuan Yuan; Gunaratne, Gemunu H; Pletcher, Scott; Roman, Gregg

    2012-01-01

    Drosophila adults, when placed into a novel open-field arena, initially exhibit an elevated level of activity followed by a reduced stable level of spontaneous activity and spend a majority of time near the arena edge, executing motions along the walls. In order to determine the environmental features that are responsible for the initial high activity and wall-following behavior exhibited during exploration, we examined wild-type and visually impaired mutants in arenas with different vertical surfaces. These experiments support the conclusion that the wall-following behavior of Drosophila is best characterized by a preference for the arena boundary, and not thigmotaxis or centrophobicity. In circular arenas, Drosophila mostly move in trajectories with low turn angles. Since the boundary preference could derive from highly linear trajectories, we further developed a simulation program to model the effects of turn angle on the boundary preference. In an hourglass-shaped arena with convex-angled walls that forced a straight versus wall-following choice, the simulation with constrained turn angles predicted general movement across a central gap, whereas Drosophila tend to follow the wall. Hence, low turn angled movement does not drive the boundary preference. Lastly, visually impaired Drosophila demonstrate a defect in attenuation of the elevated initial activity. Interestingly, the visually impaired w1118 activity decay defect can be rescued by increasing the contrast of the arena's edge, suggesting that the activity decay relies on visual detection of the boundary. The arena boundary is, therefore, a primary object of exploration for Drosophila. PMID:22574279

  5. A brittle-ductile high- and low-angle fault related to the Kea extensional detachment (W Cyclades., Greece)

    NASA Astrophysics Data System (ADS)

    Rockenschaub, M.; Grasemann, B.; Iglseder, C.; Rice, A. H. N.; Schneider, D.; Zamolyi, A.

    2010-05-01

    Roll-back of the African Plate within the Eurasian-African collision zone since the Oligocene/Miocene led to extension in the Cyclades along low-angle normal fault zones and exhumation of rocks from near the brittle-ductile transition zone. On the island of Kea (W Cyclades), which represents such a crustal scale low-angle fault zone with top-to-SSW kinematics, remote sensing analysis of brittle fault lineaments in the Pissis area (W Kea) demonstrates two dominant strike directions: ca. NE-SW and NW-SE. From the north of Pisses southwards, the angle between the two main fault directions changes gradually from a rhombohedral geometry (ca. 50°/130° angle between faults, with the acute angle facing westwards) to an orthogonal geometry. The aim of this study is the development of this fault system. We investigate, if this fault system is related to the Miocene extension or if it is related to a later overprinting event (e.g. the opening of the Corinth) Field observations revealed that the investigated lineaments are high-angle (50-90° dip) brittle/ductile conjugate, faults. Due to the lack of marker layers offsets could only rarely be estimated. Locally centimetre thick marble layers in the greenschists suggest a displacement gradient along the faults with a maximum offset of less than 60 cm. Large displacement gradients are associated with a pronounced ductile fault drag in the host rocks. In some instances, high-angle normal faults were observed to link kinematically with low-angle, top-to-SSW brittle/ductile shear bands. Both the high- and the low-angle faults have a component of ductile shear, which is overprinted by brittle deformation mechanisms. In thin-section, polyphase mode-2 cracks are filled mainly with calcite and quartz (ultra)cataclasites, sometimes followed by further opening with fluid-related iron-rich carbonate (ankeritic) precipitation. CL analysis reveals several generations of cements, indicating multiple phases of cataclastic deformation and fluid infiltration. Ar/Ar white mica data from Pisses constrain ductile deformation to ca. 20 Ma. Since the high-angle faults show a continuum from ductile to brittle deformation, the Ar/Ar cooling ages suggest that faulting must have occurred in the Miocene. Consequently the high-angle faulting was genetically related to the SSW-directed low-angle extensional event and does not represent a later overprint related to a different kinematic event.

  6. Large-angle cosmic microwave background anisotropies in an open universe

    NASA Technical Reports Server (NTRS)

    Kamionkowski, Marc; Spergel, David N.

    1994-01-01

    If the universe is open, scales larger than the curvature scale may be probed by observation of large-angle fluctuations in the cosmic microwave background (CMB). We consider primordial adiabatic perturbations and discuss power spectra that are power laws in volume, wavelength, and eigenvalue of the Laplace operator. Such spectra may have arisen if, for example, the universe underwent a period of `frustated' inflation. The resulting large-angle anisotropies of the CMB are computed. The amplitude generally increases as Omega is decreased but decreases as h is increased. Interestingly enough, for all three Ansaetze, anisotropies on angular scales larger than the curvature scale are suppressed relative to the anisotropies on scales smaller than the curvature scale, but cosmic variance makes discrimination between various models difficult. Models with 0.2 approximately less than Omega h approximately less than 0.3 appear compatible with CMB fluctuations detected by Cosmic Background Explorer Satellite (COBE) and the Tenerife experiment and with the amplitude and spectrum of fluctuations of galaxy counts in the APM, CfA, and 1.2 Jy IRAS surveys. COBE normalization for these models yields sigma(sub 8) approximately = 0.5 - 0.7. Models with smaller values of Omega h when normalized to COBE require bias factors in excess of 2 to be compatible with the observed galaxy counts on the 8/h Mpc scale. Requiring that the age of the universe exceed 10 Gyr implies that Omega approximately greater than 0.25, while requiring that from the last-scattering term in the Sachs-Wolfe formula, large-angle anisotropies come primarily from the decay of potential fluctuations at z approximately less than 1/Omega. Thus, if the universe is open, COBE has been detecting temperature fluctuations produced at moderate redshift rather than at z approximately 1300.

  7. Accuracy of percutaneous pedicle screws for thoracic and lumbar spine fractures compared with open technique.

    PubMed

    Paredes, Igor; Panero, Irene; Cepeda, Santiago; Castaño-Leon, Ana M; Jimenez-Roldan, Luis; Perez-Nuñez, Ángel; Alén, Jose A; Lagares, Alfonso

    2018-06-14

    This study aimed to compare the accuracy of screw placement between open pedicle screw fixation and percutaneous pedicle screw fixation (MIS) for the treatment of thoracolumbar spine fractures (TSF). Forty-nine patients with acute TSF who were treated with transpedicular screw fixation from January 2013 to December 2016 were retrospectively reviewed. The patients were divided into Open and MIS groups. Laminectomy was performed in either group if needed. The accuracy of the screw placement, the evolution of the Cobb sagital angle postoperatively and at 12-month follow up and the neurological status were recorded. AO type of fracture and TLICS score were also recorded. Mean age was 42 years old. Mean TLICS score was 6,29 and 5,96 for open and MIS groups respectively. Twenty five MIS and 24 open surgeries were performed, and 350 (175 in each group) screws were inserted (7,14 per patient). Twenty-four and 13 screws were considered ̈out ̈ in the open and MIS groups respectively (Odds ratio 1,98. 0,97-4,03 p=0,056). The Cobb sagittal angle went from 13,3o to 4,5o and from 14,9o to 8,2o in the Open and MIS groups respectively (both p<0,0001). Loss of correction at 12-month follow up was 3,2o and 4,2o for the open and MIS groups respectively. No neurological worsening was observed. For the treatment of acute thoracolumbar fractures, the MIS technique seems to achieve similar results to the open technique in relation to neurological improvement and deformity correction, while placing the screws more accurately.

  8. Angle-resolved photoemission spectroscopy studies of metallic surface and interface states of oxide insulators

    NASA Astrophysics Data System (ADS)

    Plumb, Nicholas C.; Radović, Milan

    2017-11-01

    Over the last decade, conducting states embedded in insulating transition metal oxides (TMOs) have served as gateways to discovering and probing surprising phenomena that can emerge in complex oxides, while also opening opportunities for engineering advanced devices. These states are commonly realized at thin film interfaces, such as the well-known case of LaAlO3 (LAO) grown on SrTiO3 (STO). In recent years, the use of angle-resolved photoemission spectroscopy (ARPES) to investigate the k-space electronic structure of such materials led to the discovery that metallic states can also be formed on the bare surfaces of certain TMOs. In this topical review, we report on recent studies of low-dimensional metallic states confined at insulating oxide surfaces and interfaces as seen from the perspective of ARPES, which provides a direct view of the occupied band structure. While offering a fairly broad survey of progress in the field, we draw particular attention to STO, whose surface is so far the best-studied, and whose electronic structure is probably of the most immediate interest, given the ubiquitous use of STO substrates as the basis for conducting oxide interfaces. The ARPES studies provide crucial insights into the electronic band structure, orbital character, dimensionality/confinement, spin structure, and collective excitations in STO surfaces and related oxide surface/interface systems. The obtained knowledge increases our understanding of these complex materials and gives new perspectives on how to manipulate their properties.

  9. Progression of trunk imbalance in adolescent idiopathic scoliosis with a thoracolumbar/lumbar curve: is it predictable at the initial visit?

    PubMed

    Hwang, Chang Ju; Lee, Choon Sung; Lee, Dong-Ho; Cho, Jae Hwan

    2017-11-01

    OBJECTIVE Progression of trunk imbalance is an important finding during follow-up of patients with adolescent idiopathic scoliosis (AIS). Nevertheless, no factors that predict progression of trunk imbalance have been identified. The purpose of this study was to identify parameters that predict progression of trunk imbalance in cases of AIS with a structural thoracolumbar/lumbar (TL/L) curve. METHODS This study included 105 patients with AIS and a structural TL/L curve who were followed up at an outpatient clinic. Patients with trunk imbalance (trunk shift ≥ 20 mm) at the initial visit were excluded. All patients were followed up for more than 2 years. Patients were divided into the following groups according to progression of trunk imbalance: 1) Group P, trunk shift ≥ 20 mm at the final visit and degree of progression ≥ 10 mm; and 2) Group NP, trunk shift < 20 mm at the final visit or degree of progression < 10 mm. Radiological parameters included Cobb angle, upper end vertebrae and lower end vertebrae (LEV), LEV tilt, disc wedge angle between LEV and LEV+1, trunk shift, apical vertebral translation, and apical vertebral rotation (AVR). Each parameter was compared between groups. Radiological parameters were assessed at every visit using whole-spine standing anteroposterior radiographs. RESULTS Among the 105 patients examined, 13 showed trunk imbalance with progression ≥ 10 mm at the final visit (Group P). Multivariate logistic regression analysis identified a lower Risser grade (p = 0.002) and a greater initial AVR (p = 0.020) as predictors of progressive trunk imbalance. A change in LEV tilt during follow-up was associated with trunk imbalance (p = 0.001). CONCLUSIONS Risser grade and AVR measured at the initial visit may predict progression of trunk imbalance. Surgeons should consider the risk of progressive trunk imbalance if patients show skeletal immaturity and a greater AVR at the initial visit.

  10. Progression of pectinate ligament dysplasia over time in two populations of Flat-Coated Retrievers.

    PubMed

    Pearl, Rose; Gould, David; Spiess, Bernhard

    2015-01-01

    Two of the authors (DG, BS) independently observed that a number of Flat-Coated Retrievers (FCRs) previously unaffected by pectinate ligament dysplasia (PLD) appeared to develop the condition later in life. This study was instigated to investigate progression of PLD within individual dogs over time. Flat-Coated Retrievers that had previously undergone gonioscopy under the UK/ECVO hereditary eye schemes were included in the study. A second gonioscopic examination was performed 1.92-12.58 years later (mean 6, median 5.75 years) and the results compared. 39 FCR (17 males, 22 females) in the UK and 57 FCR (27 males, 30 females) in Switzerland were included. Slit-lamp biomicroscopy, indirect ophthalmoscopy, and gonioscopy were performed in all dogs. Gonioscopy allowed classification as either unaffected or affected; percentage of the iridocorneal drainage angle (ICA) affected by PLD was determined, before calculating progression observed as mild, moderate, or severe. 39 of 96 (40.6%) dogs demonstrated progression of PLD (P < 0.0001). Of these, 13 of 96 (13.5%) were classified as mild progression (from either unaffected to 10-20% or 10-20% to 20-90% ICA affected). Progression was more extensive in 26 of 96 (27.1%) dogs (P < 0.0001), of which 12 of 96 (12.5%) went from unaffected to severe PLD of >90% ICA affected, consistent with a high risk of glaucoma. To the authors' knowledge, this is the first report describing progression of PLD in individual dogs over time, in a breed affected by primary, angle closure glaucoma. © 2013 American College of Veterinary Ophthalmologists.

  11. Optimal Control of Airfoil Flow Separation using Fluidic Excitation

    NASA Astrophysics Data System (ADS)

    Shahrabi, Arireza F.

    This thesis deals with the control of flow separation around a symmetric airfoils with the aid of multiple synthetic jet actuators (SJAs). CFD simulation methods have been implemented to uncover the flow separation regimes and associated properties such as frequencies and momentum ratio. In the first part of the study, the SJA was studied thoroughly. Large Eddy Simulations (LES) were performed for one individual cavity; the time history of SJA of the outlet velocity profile and the net momentum imparted to the flow were analyzed. The studied SJA is asymmetrical and operates with the aid of a piezoelectric (PZT) ceramic circular plate actuator. A three-dimensional mesh for the computational domain of the SJA and the surrounding volume was developed and was used to evaluate the details of the airflow conditions inside the SJA as well as at the outlet. The vibration of the PZT ceramic actuator was used as a boundary condition in the computational model to drive the SJA. Particular attention was given to developing a predictive model of the SJA outlet velocity. Results showed that the SJA velocity output is correlated to the PZT ceramic plate vibration, especially for the first frequency mode. SJAs are a particular class of zero net mass flux (ZNMF) fluidic devices with net imparted momentum to the flow. The net momentum imparted to the flow in the separated region is such that positive enhancement during AFC operations is achieved. Flows around the NACA 0015 airfoil were simulated for a range of operating conditions. Attention was given to the active open and closed loop control solutions for an airfoil with SJA at different angles of attack and flap angles. A large number of simulations using RANS & LES models were performed to study the effects of the momentum ratio (Cμ) in the range of 0 to 11% and of the non-dimensional frequency, F+, in the range of 0 to 2 for the control of flow separation at a practical angle of attack and flap angle. The optimum value of Cμ as well as F+ were evaluated and discussed. The computational model predictions showed good agreement with the experimental data. It was observed that different angles of attack and flap angles have different requirements for the minimum value of the momentum coefficient, Cμ, in order for the SJA to be effective for control of separation. It was also found that the variation of F + noticeably affects the lift and drag forces acting on the airfoil. The optimum values of parameters during open loop control simulations have been applied in order to introduce the optimal open loop control outcome. An innovative approach has been implemented to formulate optimal frequencies and momentum ratios of vortex shedding which depends on angle of attack and static pressure of the separation zone in the upper chord. Optimal open loop results have been compared with the optimal closed loop results. Cumulative case studies in the matter of angle of attacks, flap angles, Re, Cμ and F+ provide a convincing collection of evidence to the following conclusion. An improvement of a direct closed loop control was demonstrated, and an analytical formula describing the properties of a separated flow and vortex shedding was proposed. Best AFC solutions are offered by providing optimal frequencies and momentum ratios at a variety of flow conditions.

  12. The effect of transverse crack upon parametric instability of a rotor-bearing system with an asymmetric disk

    NASA Astrophysics Data System (ADS)

    Han, Qinkai; Chu, Fulei

    2012-12-01

    It is well known that either the asymmetric disk or transverse crack brings parametric inertia (or stiffness) excitation to the rotor-bearing system. When both of them appear in a rotor system, the parametric instability behaviors have not gained sufficient attentions. Thus, the effect of transverse crack upon parametric instability of a rotor-bearing system with an asymmetric disk is studied. First, the finite element equations of motion are established for the asymmetric rotor system. Both the open and breathing transverse cracks are taken into account in the model. Then, the discrete state transition matrix (DSTM) method is introduced for numerically acquiring the instability regions. Based upon these, some computations for a practical asymmetric rotor system with open or breathing transverse crack are conducted, respectively. Variations of the primary and combination instability regions induced by the asymmetric disk with the crack depth are observed, and the effect of the orientation angle between the crack and asymmetric disk on various instability regions are discussed in detail. It is shown that for the asymmetric angle around 0, the existence of transverse (either open or breathing) crack has attenuation effect upon the instability regions. Under certain crack depth, the instability regions could be vanished by the transverse crack. When the asymmetric angle is around π/2, increasing the crack depth would enhance the instability regions.

  13. Exclusion of candidate genes from the chromosome 1q juvenile glaucoma region and mapping of the peripheral cannabis receptor gene (CNR2) to chromosome 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sunden, S.L.F.; Nichols, B.E.; Alward, W.L.M.

    Juvenile onset primary open angle glaucoma has been mapped by linkage to 1q21-q31. Several candidate genes were evaluated in the same family used to identify the primary linkage. Atrionatriuretic peptide receptor A (NPR1) and laminin C1 (LAMC1) have been previously mapped to this region and could putatively play a role in the pathogenesis of glaucoma. A third gene, the peripheral cannabis receptor (CNR2) was not initially mapped in humans but was a candidate because of the relief that cannabis affords some patients with primary open angle glaucoma. Microsatellites associated with NPR1 and LAMC1 revealed multiple recombinations in affected members ofmore » this pedigree. CNR2 was shown to be on chromosome 1 by PCR amplification of a 150 bp fragment of the 3{prime} untranslated region in monochromosomal somatic cell hybrids (NIGMS panel No. 2). These primers also revealed a two allele single strand conformation polymorphism which showed multiple recombinants with juvenile onset primary open angle glaucoma in large pedigrees, segregating this disorder. The marker was then mapped to 1p34-p36 by linkage, with the most likely location between liver alkaline phosphatase (ALPL) and alpha-L-1 fucosidase (FUCA1).« less

  14. Application of Bayes' to the prediction of referral decisions made by specialist optometrists in relation to chronic open angle glaucoma.

    PubMed

    Gurney, J C; Ansari, E; Harle, D; O'Kane, N; Sagar, R V; Dunne, M C M

    2018-02-09

    To determine the accuracy of a Bayesian learning scheme (Bayes') applied to the prediction of clinical decisions made by specialist optometrists in relation to the referral refinement of chronic open angle glaucoma. This cross-sectional observational study involved collection of data from the worst affected or right eyes of a consecutive sample of cases (n = 1,006) referred into the West Kent Clinical Commissioning Group Community Ophthalmology Team (COT) by high street optometrists. Multilevel classification of each case was based on race, sex, age, family history of chronic open angle glaucoma, reason for referral, Goldmann Applanation Tonometry (intraocular pressure and interocular asymmetry), optic nerve head assessment (vertical size, cup disc ratio and interocular asymmetry), central corneal thickness and visual field analysis (Hodapp-Parrish-Anderson classification). Randomised stratified tenfold cross-validation was applied to determine the accuracy of Bayes' by comparing its output to the clinical decisions of three COT specialist optometrists; namely, the decision to discharge, follow-up or refer each case. Outcomes of cross-validation, expressed as means and standard deviations, showed that the accuracy of Bayes' was high (95%, 2.0%) but that it falsely discharged (3.4%, 1.6%) or referred (3.1%, 1.5%) some cases. The results indicate that Bayes' has the potential to augment the decisions of specialist optometrists.

  15. Femoral articular geometry and patellofemoral stability.

    PubMed

    Iranpour, Farhad; Merican, Azhar M; Teo, Seow Hui; Cobb, Justin P; Amis, Andrew A

    2017-06-01

    Patellofemoral instability is a major cause of anterior knee pain. The aim of this study was to examine how the medial and lateral stability of the patellofemoral joint in the normal knee changes with knee flexion and measure its relationship to differences in femoral trochlear geometry. Twelve fresh-frozen cadaveric knees were used. Five components of the quadriceps and the iliotibial band were loaded physiologically with 175N and 30N, respectively. The force required to displace the patella 10mm laterally and medially at 0°, 20°, 30°, 60° and 90° knee flexion was measured. Patellofemoral contact points at these knee flexion angles were marked. The trochlea cartilage geometry at these flexion angles was visualized by Computed Tomography imaging of the femora in air with no overlying tissue. The sulcus, medial and lateral facet angles were measured. The facet angles were measured relative to the posterior condylar datum. The lateral facet slope decreased progressively with flexion from 23°±3° (mean±S.D.) at 0° to 17±5° at 90°. While the medial facet angle increased progressively from 8°±8° to 36°±9° between 0° and 90°. Patellar lateral stability varied from 96±22N at 0°, to 77±23N at 20°, then to 101±27N at 90° knee flexion. Medial stability varied from 74±20N at 0° to 170±21N at 90°. There were significant correlations between the sulcus angle and the medial facet angle with medial stability (r=0.78, p<0.0001). These results provide objective evidence relating the changes of femoral profile geometry with knee flexion to patellofemoral stability. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Anterior Chamber Angle Shape Analysis and Classification of Glaucoma in SS-OCT Images.

    PubMed

    Ni Ni, Soe; Tian, J; Marziliano, Pina; Wong, Hong-Tym

    2014-01-01

    Optical coherence tomography is a high resolution, rapid, and noninvasive diagnostic tool for angle closure glaucoma. In this paper, we present a new strategy for the classification of the angle closure glaucoma using morphological shape analysis of the iridocorneal angle. The angle structure configuration is quantified by the following six features: (1) mean of the continuous measurement of the angle opening distance; (2) area of the trapezoidal profile of the iridocorneal angle centered at Schwalbe's line; (3) mean of the iris curvature from the extracted iris image; (4) complex shape descriptor, fractal dimension, to quantify the complexity, or changes of iridocorneal angle; (5) ellipticity moment shape descriptor; and (6) triangularity moment shape descriptor. Then, the fuzzy k nearest neighbor (fkNN) classifier is utilized for classification of angle closure glaucoma. Two hundred and sixty-four swept source optical coherence tomography (SS-OCT) images from 148 patients were analyzed in this study. From the experimental results, the fkNN reveals the best classification accuracy (99.11 ± 0.76%) and AUC (0.98 ± 0.012) with the combination of fractal dimension and biometric parameters. It showed that the proposed approach has promising potential to become a computer aided diagnostic tool for angle closure glaucoma (ACG) disease.

  17. [The questionnaire survey on glaucoma diagnosis and treatment in China (2016)].

    PubMed

    Zhang, Q; Cao, K; Kang, M T; Sun, Y X; Gan, J H; Tian, J X; Ran, A R; Zhang, X; Su, Y D; Li, S N

    2017-02-11

    Objective: To investigate the present situation of diagnosis and treatment for primary angle-closure glaucoma (PACG) and primary open-angle glaucoma (POAG) and awareness of the relevant progress among Chinese ophthalmologists. Methods: This study was a cross-sectional, non-randomized sampling survey. Participants were ophthalmologists who attended the 11st Chinese Glaucoma Society Congress during November 11 to 12, 2016. They were invited to fill out a questionnaire. The questionnaire included participants' basic information and their knowledge about glaucoma diagnosis and treatment. The data collected through questionnaire were analyzed with SAS9.4. Results: A total of 450 questionnaires were distributed and 372 valid questionnaires were retrieved, with a response rate of 82. 7%(372/450). ISGEO classification system was adopted by 58.9% (219/372) of the participants as the diagnostic criteria for PACG. Of the respondents, 48.1% (179/372) of the participants believed that "anterior chamber angle closure mechanism-based PACG classification system" was more instructive for treatment, the percentage was higher than ISGEO classification system (42.2%, 157/372). Most (72.3%, 269/372) of the participants knew the 3-minute dark room prone test, but only 27.7%(103/372) of them applied it in clinical practice. A total of 83.4%(310/372) of the participants believed that low cerebrospinal fluid pressure is a risk factor for POAG. In all, 71.8% (267/372) of the participants reported that their institutes had applied compound trabeculectomy with adjustable suture, with 76.9%(286/372) of the participants agreeing that the adjustable suture reduced the rate of complications after trabeculectomy. Conclusions: Currently, both ISGEO classification system and anterior chamber angle closure mechanism-based PACG classification system were adopted in the diagnosis and treatment of glaucoma. Low cerebrospinal fluid pressure as new risk factors for POAG has been widely acknowledged and given attentions by Chinese ophthalmologists. The 3-minute darkroom prone test and compound trabeculectomy with adjustable suture still need to be promoted. (Chin J Ophthalmol, 2017, 53: 115-120) .

  18. Wicket gate trailing-edge blowing: A method for improving off-design hydroturbine performance by adjusting the runner inlet swirl angle

    NASA Astrophysics Data System (ADS)

    Lewis, B. J.; Cimbala, J. M.; Wouden, A. M.

    2014-03-01

    At their best efficiency point (BEP), hydroturbines operate at very high efficiency. However, with the ever-increasing penetration of alternative electricity generation, it has become common to operate hydroturbines at off-design conditions in order to maintain stability in the electric power grid. This paper demonstrates a method for improving hydroturbine performance during off-design operation by injecting water through slots at the trailing edges of the wicket gates. The injected water causes a change in bulk flow direction at the inlet of the runner. This change in flow angle from the wicket gate trailing-edge jets provides the capability of independently varying the flow rate and swirl angle through the runner, which in current designs are both determined by the wicket gate opening angle. When properly tuned, altering the flow angle results in a significant improvement in turbine efficiency during off-design operation.

  19. Evaluation of eyes with relative pupillary block by indentation ultrasound biomicroscopy gonioscopy.

    PubMed

    Matsunaga, Koichi; Ito, Kunio; Esaki, Koji; Sugimoto, Kota; Sano, Toru; Miura, Katsuya; Sasoh, Mikio; Uji, Yukitaka

    2004-03-01

    To investigate changes in anterior chamber angle configuration with indentation ultrasound biomicroscopy gonioscopy of relative pupillary block (RPB). Cross-sectional study. This study included 26 eyes of 26 patients with RPB. We determined angle opening distance 500 and angle recess area using indentation ultrasound biomicroscopy gonioscopy and compared a small-sized standard eye cup with a new eye cup with an area for inducing pressure. Indentation ultrasound biomicroscopy images documented concavity of the iris in eyes with RPB. Both the new and the small standard eye cups widened the anterior chamber angle significantly (P <.0001) without causing corneal damage. Angle changes were significantly greater for the new eye cup design. Indentation ultrasound biomicroscopy gonioscopy is a useful technique for observation and diagnosis of RPB. Using a small standard or the newly designed eye cup, the procedure can be performed easily and without causing corneal damage.

  20. Angle stations in or for endless conveyor belts

    DOEpatents

    Steel, Alan

    1987-04-07

    In an angle station for an endless conveyor belt, there are presented to each incoming run of the belt stationary curved guide members (18, 19) of the shape of a major segment of a right-circular cylinder and having in the part-cylindrical portion (16 or 17) thereof rectangular openings (15) arranged in parallel and helical paths and through which project small freely-rotatable rollers (14), the continuously-changing segments of the curved surfaces of which projecting through said openings (15) are in attitude to change the direction of travel of the belt (13) through 90.degree. during passage of the belt about the part-cylindrical portion (16 or 17) of the guide member (18 or 19). The rectangular openings (15) are arranged with their longer edges lengthwise of the diagonals representing the mean of the helix but with those of a plurality of the rows nearest to each end of the part-cylindrical portion (16 or 17) slightly out of axial symmetry with said diagonals, being slightly inclined in a direction about the intersections (40) of the diagonals of the main portion of the openings, to provide a "toe-in" attitude in relation to the line of run of the endless conveyor belt.

  1. Optical coherence tomography in anterior segment imaging

    PubMed Central

    Kalev-Landoy, Maya; Day, Alexander C.; Cordeiro, M. Francesca; Migdal, Clive

    2008-01-01

    Purpose To evaluate the ability of optical coherence tomography (OCT), designed primarily to image the posterior segment, to visualize the anterior chamber angle (ACA) in patients with different angle configurations. Methods In a prospective observational study, the anterior segments of 26 eyes of 26 patients were imaged using the Zeiss Stratus OCT, model 3000. Imaging of the anterior segment was achieved by adjusting the focusing control on the Stratus OCT. A total of 16 patients had abnormal angle configurations including narrow or closed angles and plateau irides, and 10 had normal angle configurations as determined by prior full ophthalmic examination, including slit-lamp biomicroscopy and gonioscopy. Results In all cases, OCT provided high-resolution information regarding iris configuration. The ACA itself was clearly visualized in patients with narrow or closed angles, but not in patients with open angles. Conclusions Stratus OCT offers a non-contact, convenient and rapid method of assessing the configuration of the anterior chamber. Despite its limitations, it may be of help during the routine clinical assessment and treatment of patients with glaucoma, particularly when gonioscopy is not possible or difficult to interpret. PMID:17355288

  2. Genetics Home Reference: spinal muscular atrophy with progressive myoclonic epilepsy

    MedlinePlus

    ... myoclonic epilepsy Spinal muscular atrophy with progressive myoclonic epilepsy Printable PDF Open All Close All Enable Javascript ... boxes. Description Spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME) is a neurological condition that causes ...

  3. Influence of crack opening and incident wave angle on second harmonic generation of Lamb waves

    NASA Astrophysics Data System (ADS)

    Yang, Yi; Ng, Ching-Tai; Kotousov, Andrei

    2018-05-01

    Techniques utilising second harmonic generation (SHG) have proven their great potential in detecting contact-type damage. However, the gap between the practical applications and laboratory studies is still quite large. The current work is aimed to bridge this gap by investigating the effects of the applied load and incident wave angle on the detectability of fatigue cracks at various lengths. Both effects are critical for practical implementations of these techniques. The present experimental study supported by three-dimensional (3D) finite element (FE) modelling has demonstrated that the applied load, which changes the crack opening and, subsequently, the contact nonlinearity, significantly affects the amplitude of the second harmonic generated by the fundamental symmetric mode (S0) of Lamb wave. This amplitude is also dependent on the length of the fatigue crack as well as the incident wave angle. The experimental and FE results correlate well, so the modelling approach can be implemented for practical design of damage monitoring systems as well as for the evaluation of the severity of the fatigue cracks.

  4. Variability of single-leg versus double-leg stance radiographs in the varus knee.

    PubMed

    Chen, Andrew; Rich, Valerie; Bain, Elizabeth; Sterett, William I

    2009-07-01

    We evaluated measured radiographic parameter variability between single-leg stance (SLS) and double-leg stance (DLS) radiographs in patients with varus knee malalignment, indicated for high tibial osteotomy. Fifty-three consecutive knees (mean, 49 years; range, 18-79 years) were evaluated for varus thrust. SLS and DLS radiographs were obtained. A single blinded observer measured mechanical axis angles and weight-bearing line (WBL) deviation using a goniometer. Mechanical axis angles averaged 9.1 degrees (DLS) and 11.3 degrees (SLS). SLS radiographs averaged 9% greater WBL medialization than did DLS. Medial opening averaged 16.4 mm (DLS) and 18.8 mm (SLS). DLS and SLS radiographs showed no significant differences in patients without varus thrust. Patients with varus thrust demonstrated differences in mechanical axis angles (DLS, 9.4 degrees; SLS, 12.2 degrees), WBL deviation (12.1% less), medialization (DLS), and medial opening necessary for correction (DLS, 16.6 mm; SLS, 20.3 mm). In varus thrust, SLS radiographs more closely replicate dynamic knee malalignment, possibly providing more accurate measurements of angular deformity.

  5. Optimizing water permeability through the hourglass shape of aquaporins

    PubMed Central

    Gravelle, Simon; Joly, Laurent; Detcheverry, François; Ybert, Christophe; Cottin-Bizonne, Cécile; Bocquet, Lydéric

    2013-01-01

    The ubiquitous aquaporin channels are able to conduct water across cell membranes, combining the seemingly antagonist functions of a very high selectivity with a remarkable permeability. Whereas molecular details are obvious keys to perform these tasks, the overall efficiency of transport in such nanopores is also strongly limited by viscous dissipation arising at the connection between the nanoconstriction and the nearby bulk reservoirs. In this contribution, we focus on these so-called entrance effects and specifically examine whether the characteristic hourglass shape of aquaporins may arise from a geometrical optimum for such hydrodynamic dissipation. Using a combination of finite-element calculations and analytical modeling, we show that conical entrances with suitable opening angle can indeed provide a large increase of the overall channel permeability. Moreover, the optimal opening angles that maximize the permeability are found to compare well with the angles measured in a large variety of aquaporins. This suggests that the hourglass shape of aquaporins could be the result of a natural selection process toward optimal hydrodynamic transport. Finally, in a biomimetic perspective, these results provide guidelines to design artificial nanopores with optimal performances. PMID:24067650

  6. Effects of excimer laser illumination on microdrilling into an oblique polymer surface

    NASA Astrophysics Data System (ADS)

    Wu, Chih-Yang; Shu, Chun-Wei; Yeh, Zhi-Chang

    2006-08-01

    In this work, we present the experimental results of micromachining into polymethy-methacrylate exposed to oblique KrF excimer laser beams. The results of low-aspect-ratio ablations show that the ablation rate decreases monotonously with the increase of incident angle for various fluences. The ablation rate of high-aspect-ratio drilling with opening center on the focal plane is almost independent of incident angles and is less than that of low-aspect-ratio ablation. The results of high-aspect-ratio ablations show that the openings of the holes at a distance from the focal plane are enlarged and their edges are blurred. Besides, the depth of a hole in the samples oblique to the laser beam at a distance from the focal plane decreases with the increase of the distance from the focal plane. The number of deep holes generated by oblique laser beams through a matrix of apertures decreases with the increase of incident angle. Those phenomena reveal the influence of the local light intensity on microdrilling into an oblique surface.

  7. Initial Investigation of the Acoustics of a Counter-Rotating Open Rotor Model with Historical Baseline Blades in a Low-Speed Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Elliott, David M.

    2012-01-01

    A counter-rotating open rotor scale model was tested in the NASA Glenn Research Center 9- by 15-Foot Low-Speed Wind Tunnel (LSWT). This model used a historical baseline blade set with which modern blade designs will be compared against on an acoustic and aerodynamic performance basis. Different blade pitch angles simulating approach and takeoff conditions were tested, along with angle-of-attack configurations. A configuration was also tested in order to determine the acoustic effects of a pylon. The shaft speed was varied for each configuration in order to get data over a range of operability. The freestream Mach number was also varied for some configurations. Sideline acoustic data were taken for each of these test configurations.

  8. Strong-field ionization with twisted laser pulses

    NASA Astrophysics Data System (ADS)

    Paufler, Willi; Böning, Birger; Fritzsche, Stephan

    2018-04-01

    We apply quantum trajectory Monte Carlo computations in order to model strong-field ionization of atoms by twisted Bessel pulses and calculate photoelectron momentum distributions (PEMD). Since Bessel beams can be considered as an infinite superposition of circularly polarized plane waves with the same helicity, whose wave vectors lie on a cone, we compared the PEMD of such Bessel pulses to those of a circularly polarized pulse. We focus on the momentum distributions in propagation direction of the pulse and show how these momentum distributions are affected by experimental accessible parameters, such as the opening angle of the beam or the impact parameter of the atom with regard to the beam axis. In particular, we show that we can find higher momenta of the photoelectrons, if the opening angle is increased.

  9. Educating the glaucoma patient.

    PubMed Central

    Rosenthal, A. R.; Zimmerman, J. F.; Tanner, J.

    1983-01-01

    Forty-nine patients with open-angle glaucoma and 32 controls were studied at each of 2 medical centres, one in California and one in England. A 12-point questionnaire was answered before, immediately after, and 6 months after viewing a 6 minute video film about glaucoma. The English glaucoma patients and controls showed lower initial knowledge than their American counterparts. Immediately after the film all groups had substantially improved their knowledge by answering 78-88% of the questions correctly. Recall study showed that both American groups had retained more than their British counterparts and that glaucoma patients retained more knowledge of their disease than did controls. The use of an educational video film in an outpatient setting is a simple and economical method of patient education applicable to both American and British subjects with open-angle glaucoma. PMID:6671096

  10. On the 'flip-flop' instability of Bondi-Hoyle accretion flows

    NASA Technical Reports Server (NTRS)

    Livio, Mario; Soker, Noam; Matsuda, Takuya; Anzer, Ulrich

    1991-01-01

    A simple physical interpretation is advanced by means of an analysis of the shock cone in the accretion flows past a compact object and with an examination of the accretion-line stability analyses. The stability of the conical shock is examined against small angular deflections with attention given to several simplifying assumptions. A line instability is identified in the Bondi-Hoyle accretion flows that leads to the formation of a large opening-angle shock. When the opening angle becomes large the instability becomes irregular oscillation. The analytical methodology is compared to previous numerical configurations that demonstrate different shock morphologies. The Bondi-Hoyle accretion onto a compact object is concluded to generate a range of nonlinear instabilities in both homogeneous and inhomogeneous cases with a quasiperiodic oscillation in the linear regime.

  11. Role of oxidative stress enzymes in open-angle glaucoma.

    PubMed

    Yildirim, O; Ateş, N A; Ercan, B; Muşlu, N; Unlü, A; Tamer, L; Atik, U; Kanik, A

    2005-05-01

    To investigate the role of oxidative stress and lipid peroxidation in the pathogenesis of primary open-angle glaucoma (POAG). The activities of myeloperoxidase (MPO), catalase (CAT), and the levels of plasma malondialdehyde (MDA) were measured in 40 (15 men and 25 women) patients with POAG and 60 (30 men and 30 women) healthy controls. There was no significant difference in the activities of CAT and MPO between the POAG patients and the controls. However, the plasma MDA level was significantly higher in patients than the controls. The results of this preliminary study suggest that the possible alterations of plasma MDA levels may be associated with the pathogenesis of POAG, but further research is needed to understand the role of oxidative damage in this important disorder of aging.

  12. Stationary Digital Tomosynthesis System for Early Detection of Breast Tumors

    DTIC Science & Technology

    2012-05-01

    Vol. 5745. 2005. 14. Y. Zhang, et al., A comparative study of limited-angle cone-beam reconstruction methods 505 for breast tomosynthesis. Med...opening angl em integratio designed line nia Dimension determine the try calibration th the detector ain is sent fro between XC urce not fou here...screening mammography. AJR, 2007. 189: p. 616. 12. P. Baldelli, et al., A prototype of a quasi-monochromatic system for mammography applications . Phys

  13. Changes in speed skating velocity in relation to push-off effectiveness.

    PubMed

    Noordhof, Dionne A; Foster, Carl; Hoozemans, Marco J M; de Koning, Jos J

    2013-03-01

    Speed skating posture, or technique, is characterized by the push-off angle or effectiveness (e), determined as the angle between the push-off leg and the ice; the preextension knee angle (θ(0)); and the trunk angle (θ(1)). Together with muscle-power output and environmental conditions, skating posture, or technique, determines velocity (v). To gain insight into technical variables that are important to skate efficiently and perform well, e, θ(0), θ(1), and skating v were determined every lap during a 5000-m World Cup. Second, the authors evaluated if changes (Δ) in e, θ(0), and θ(1) are associated with Δv. One camera filmed the skaters from a frontal view, from which e was determined. Another camera filmed the skaters from a sagittal view, from which θ(0) and θ(1) were determined. Radio-frequency identification tags around the ankles of the skaters measured v. During the race, e progressively increased and v progressively decreased, while θ(0) and θ(1) showed a less consistent pattern of change. Generalized estimating equations showed that Δe is significantly associated with Δv over the midsection of the race (β = -0.10, P < .001) and that Δθ(0) and Δθ(1) are not significantly associated with Δv. The decrease in skating v over the race is not due to increases in power losses to air friction, as knee and trunk angle were not significantly associated with changes in velocity. The decrease in velocity can be partly ascribed to the decrease in effectiveness, which reflects a decrease in power production associated with fatigue.

  14. Three-dimensional orientation and location-dependent varying rules of radiographic angles of the acetabular cup.

    PubMed

    Zhao, Jing-Xin; Su, Xiu-Yun; Zhao, Zhe; Xiao, Ruo-Xiu; Zhang, Li-Cheng; Tang, Pei-Fu

    2018-02-17

    The aim of this study is to demonstrate the varying rules of radiographic angles following varying three-dimensional (3D) orientations and locations of cup using an accurate mathematical model. A cone model is established to address the quantitative relationship between the opening circle of cup and its ellipse projection on radiograph. The varying rules of two-dimensional (2D) radiographic anteversion (RA) and inclination (RI) angles can be analyzed. When the centre of cup is located above X-ray source, with proper 3D RI/RA angles, 2D RA angle can be equal to its 3D counterpart, and 2D RI angle is usually greater than its 3D counterpart. Except for the original point on hip-centered anterior-posterior radiograph, there is no area on radiograph where both 2D RA and RI angles are equal to their 3D counterparts simultaneously. This study proposes an innovative model for accurately explaining how 2D RA/RI angles of cup are varying following different 3D RA/RI angles and location of cup. The analysis results provide clinicians an intuitive grasp of knowledge about 2D RA/RI angles greater or smaller than their 3D counterparts post-operatively. The established model may allow determining the effects of pelvic rotations on 2D radiographic angles of cup.

  15. Effects of different foot progression angles and platform settings on postural stability and fall risk in healthy and medial knee osteoarthritic adults.

    PubMed

    Khan, Saad Jawaid; Khan, Soobia Saad; Usman, Juliana; Mokhtar, Abdul Halim; Abu Osman, Noor Azuan

    2018-02-01

    This study aims to investigate the effects of varying toe angles at different platform settings on Overall Stability Index of postural stability and fall risk using Biodex Balance System in healthy participants and medial knee osteoarthritis patients. Biodex Balance System was employed to measure postural stability and fall risk at different foot progression angles (ranging from -20° to 40°, with 10° increments) on 20 healthy (control group) and 20 knee osteoarthritis patients (osteoarthritis group) randomly (age: 59.50 ± 7.33 years and 61.50 ± 8.63 years; body mass: 69.95 ± 9.86 kg and 70.45 ± 8.80 kg). Platform settings used were (1) static, (2) postural stability dynamic level 8 (PS8), (3) fall risk levels 12 to 8 (FR12) and (4) fall risk levels 8 to 2 (FR8). Data from the tests were analysed using three-way mixed repeated measures analysis of variance. The participant group, platform settings and toe angles all had a significant main effect on balance ( p ≤ 0.02). Platform settings had a significant interaction effect with participant group F(3, 144) = 6.97, p < 0.01 and toe angles F(21, 798) = 2.83, p < 0.01. Non-significant interactions were found for group × toe angles, F(7, 266) = 0.89, p = 0.50, and for group × toe angles × settings, F(21, 798) = 1.07, p = 0.36. The medial knee osteoarthritis group has a poorer postural stability and increased fall risk as compared to the healthy group. Changing platform settings has a more pronounced effect on balance in knee osteoarthritis group than in healthy participants. Changing toe angles produced similar effects in both the participant groups, with decreased stability and increased fall risk at extreme toe-in and toe-out angles.

  16. 5m RPV for Exploring Joined Wing Gust Response

    DTIC Science & Technology

    2009-12-01

    an outer layer of light glass scrim used as the first layer. Varying layers of carbon cloth are used and then the core material is added. In this...for various angles of attack and sideslip angles. A parametric model is developed using Phoenix Integration’s Model Center Software (MC). This model...by the ground control software and finally a piece of real-time footage taken from the on-board, gimbaled camera. 2009 Progress Report 27

  17. Specific exercises reduce brace prescription in adolescent idiopathic scoliosis: a prospective controlled cohort study with worst-case analysis.

    PubMed

    Negrini, Stefano; Zaina, Fabio; Romano, Michele; Negrini, Alessandra; Parzini, Silvana

    2008-06-01

    To compare the effect of Scientific Exercises Approach to Scoliosis (SEAS) exercises with "usual care" rehabilitation programmes in terms of the avoidance of brace prescription and prevention of curve progression in adolescent idiopathic scoliosis. Prospective controlled cohort observational study. Seventy-four consecutive outpatients with adolescent idiopathic scoliosis, mean 15 degrees (standard deviation 6) Cobb angle, 12.4 (standard deviation 2.2) years old, at risk of bracing who had not been treated previously. Thirty-five patients were included in the SEAS exercises group and 39 in the usual physiotherapy group. The primary outcome included the number of braced patients, Cobb angle and the angle of trunk rotation. There were 6.1% braced patients in the SEAS exercises group vs 25.0% in the usual physiotherapy group. Failures of treatment in the worst-case analysis were 11.5% and 30.8%, respectively. In both cases the differences were statistically significant. Cobb angle improved in the SEAS exercises group, but worsened in the usual physiotherapy group. In the SEAS exercises group, 23.5% of patients improved and 11.8% worsened, while in the usual physiotherapy group 11.1% improved and 13.9% worsened. These data confirm the effectiveness of exercises in patients with scoliosis who are at high risk of progression. Compared with non-adapted exercises, a specific and personalized treatment (SEAS) appears to be more effective.

  18. Extended-range tiltable micromirror

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Allen, James J; Wiens, Gloria J; Bronson, Jessica R

    A tiltable micromirror device is disclosed in which a micromirror is suspended by a progressive linkage with an electrostatic actuator (e.g. a vertical comb actuator or a capacitive plate electrostatic actuator) being located beneath the micromirror. The progressive linkage includes a pair of torsion springs which are connected together to operate similar to a four-bar linkage with spring joints. The progressive linkage provides a non-linear spring constant which can allow the micromirror to be tilted at any angle within its range substantially free from any electrostatic instability or hysteretic behavior.

  19. Closed Versus Open Supracondylar Fractures of the Humerus in Children: A Comparison of Clinical and Radiographic Presentation and Results.

    PubMed

    Lewine, Eliza; Kim, Jaehon M; Miller, Patricia E; Waters, Peter M; Mahan, Susan T; Snyder, Brian; Hedequist, Daniel; Bae, Donald S

    2018-02-01

    The purpose of this investigation was to compare the presentation and postoperative results of children treated for open and closed, completely displaced type III supracondylar humerus fractures (SCFs). Thirty patients with open and 66 patients with closed, completely displaced type III SCFs were evaluated. Open fractures underwent irrigation and debridement, and all patients were treated by open or closed reduction and pin fixation. Medical records were reviewed to obtain demographic information as well as preoperative and postoperative clinical data regarding mechanism of injury, neurovascular status, associated injuries, postoperative range of motion, infections, and pain. Radiographs were evaluated to quantify displacement, Baumann's angle, humeral capitellar angle, position of the anterior humeral line, and adequacy of reduction. Outcomes were assessed using Flynn criteria. Mean clinical follow-up for the open and closed fracture groups was 8.9 and 5.7 months, respectively. Both groups were similar with respect to age, sex distribution, weight and body mass index, laterality of involvement, and mechanism of injury. At presentation, 35% of closed SCFs and 23% of open SCFs presented with abnormal neurovascular status. There was a higher prevalence of diminished/absent pulses or distal limb ischemia in patients with open injuries (27%) compared with closed fractures (18%). Conversely, severely displaced closed fractures were more commonly associated with nerve injury/palsy at presentation (35%) than those with open fractures (23%). Spontaneous nerve recovery was seen in 87% within 3 to 6 months. Postoperative loss of reduction and malunion were more common in the closed fracture group. However, 84% of patients achieved good-to-excellent results by Flynn criteria, with no appreciable difference based upon open versus closed fractures. With timely wound and fracture treatment, the clinical and radiographic results of children treated for open SCFs is similar to those with closed type III injuries, with little increased risk for infection, malunion, or neurovascular compromise. Level III.

  20. Comparing self-guided learning and educator-guided learning formats for simulation-based clinical training.

    PubMed

    Brydges, Ryan; Carnahan, Heather; Rose, Don; Dubrowski, Adam

    2010-08-01

    In this paper, we tested the over-arching hypothesis that progressive self-guided learning offers equivalent learning benefit vs. proficiency-based training while limiting the need to set proficiency standards. We have shown that self-guided learning is enhanced when students learn on simulators that progressively increase in fidelity during practice. Proficiency-based training, a current gold-standard training approach, requires achievement of a criterion score before students advance to the next learning level. Baccalaureate nursing students (n = 15/group) practised intravenous catheterization using simulators that differed in fidelity (i.e. students' perceived realism). Data were collected in 2008. Proficiency-based students advanced from low- to mid- to high-fidelity after achieving a proficiency criterion at each level. Progressive students self-guided their progression from low- to mid- to high-fidelity. Yoked control students followed an experimenter-defined progressive practice schedule. Open-ended students moved freely between the simulators. One week after practice, blinded experts evaluated students' skill transfer on a standardized patient simulation. Group differences were examined using analyses of variance. Proficiency-based students scored highest on the high-fidelity post-test (effect size = 1.22). An interaction effect showed that the Progressive and Open-ended groups maintained their performance from post-test to transfer test, whereas the Proficiency-based and Yoked control groups experienced a significant decrease (P < 0.05). Surprisingly, most Open-ended students (73%) chose the progressive practice schedule. Progressive training and proficiency-based training resulted in equivalent transfer test performance, suggesting that progressive students effectively self-guided when to transition between simulators. Students' preference for the progressive practice schedule indicates that educators should consider this sequence for simulation-based training.

  1. Twenty-four hour intraocular pressure monitoring with the SENSIMED Triggerfish contact lens: effect of body posture during sleep.

    PubMed

    Beltran-Agulló, Laura; Buys, Yvonne M; Jahan, Farzana; Shapiro, Colin M; Flanagan, John G; Cheng, Jason; Trope, Graham E

    2017-10-01

    To determine the difference in relative intraocular pressure (IOP) measured by the SENSIMED Triggerfish (TF) contact lens in flat compared with 30° head-up sleeping positions in patients with progressive primary open-angle glaucoma or normotensive glaucoma, based on recent or recurrent disc haemorrhage. Prospective, randomised, cross-over, open-label comparative study. IOP was monitored for 24 hours using TF on two separate sessions. Patients were randomly assigned to sleep flat one night and 30° head-up the other. Outputs in arbitrary units were obtained. Sleep and wake periods were defined as 22:00-6:00 and 8:00-22:00, respectively. Mean TF values during sleep and wake periods and wake-sleep and sleep-wake slopes were calculated for each session. TF output signals were compared between positions. Twelve subjects completed the study. Significant mean positive slopes were noted during the sleep period for both positions (p<0.01). No significant differences in the TF mean values were observed between positions (p=0.51). Six (54%) subjects had mean TF values significantly higher during the flat supine session, while four (36%) subjects had higher values during the head-up session. A significant increase in Goldmann IOP (p=0.001) and TF (p=0.02) measurements were observed after 24 hours of TF wear ('drift phenomenon'). Sleep position affects IOP as measured by TF in some patients with progressive glaucoma. The upward drift in TF output detected in >50% of the subjects requires further investigation to establish whether the increased output values over time are an artefact induced by the TF or a real change in IOP. NCT01351779. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  2. Correlation between clinical fetal head station and sonographic angle of progression during the second stage of labor.

    PubMed

    Perlman, Sharon; Kivilevitch, Zvi; Moran, Orit; Katorza, Eldad; Kees, Salim; Achiron, Reuven; Gilboa, Yinon

    2017-08-04

    To investigate the correlation between the angle of progression and the clinical fetal head station (FHS) during the second stage of labor, and to build reference range. A prospective, observational study was conducted. Women carrying singleton term pregnancies were enrolled during the second stage of labor. FHS was assessed manually by a senior obstetrician, while the angle of progression (AOP) was assessed by transperineal ultrasound (TPU). Both examiners were blinded to each others results. The correlation between the sonographic AOP and the clinical FHS was analyzed. Seventy patients comprised the study group. Clinical FHS demonstrated an excellent correlation with the sonographic measurement of AOP (Pearson's Correlation 0.642, p < 0.001). This correlation was best described by a cubic regression according to the formula: 123.800 + 10.290 × FHS -2.889 * FHS +0.910, (r 2  = 0.423, p < .001). After aggregation of the mean AOP per FHS, the relative predicted centiles values and standard deviation were calculated. The mean Z score between measured and predicted values of the AOP for a given FHS was 0.007 (range -0.13 to +0.006). Our results demonstrate a significant correlation between the clinical FHS and the TPU measured AOP. These standardized sonographic values may serve the obstetrician as a reliable, objective auxiliary tool for the evaluation of the FHS during the second stage of labor.

  3. The effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle-closure glaucoma (EAGLE): study protocol for a randomized controlled trial

    PubMed Central

    2011-01-01

    Background Glaucoma is the leading cause of irreversible blindness. Although primary open-angle glaucoma is more common, primary angle-closure glaucoma (PACG) is more likely to result in irreversible blindness. By 2020, 5·3 million people worldwide will be blind because of PACG. The current standard care for PACG is a stepped approach of a combination of laser iridotomy surgery (to open the drainage angle) and medical treatment (to reduce intraocular pressure). If these treatments fail, glaucoma surgery (eg, trabeculectomy) is indicated. It has been proposed that, because the lens of the eye plays a major role in the mechanisms leading to PACG, early clear lens extraction will improve glaucoma control by opening the drainage angle. This procedure might reduce the need for drugs and glaucoma surgery, maintain good visual acuity, and improve quality of life compared with standard care. EAGLE aims to evaluate whether early lens extraction improves patient-reported, clinical outcomes, and cost-effectiveness, compared with standard care. Methods/Design EAGLE is a multicentre pragmatic randomized trial. All people presenting to the recruitment centres in the UK and east Asia with newly diagnosed PACG and who are at least 50 years old are eligible. The primary outcomes are EQ-5D, intraocular pressure, and incremental cost per quality adjusted life year (QALY) gained. Other outcomes are: vision and glaucoma-specific patient-reported outcomes, visual acuity, visual field, angle closure, number of medications, additional surgery (e.g., trabeculectomy), costs to the health services and patients, and adverse events. A single main analysis will be done at the end of the trial, after three years of follow-up. The analysis will be based on all participants as randomized (intention to treat). 400 participants (200 in each group) will be recruited, to have 90% power at 5% significance level to detect a difference in EQ-5D score between the two groups of 0·05, and a mean difference in intraocular pressure of 1·75 mm Hg. The study will have 80% power to detect a difference of 15% in the glaucoma surgery rate. Trial Registration: ISRCTN44464607. PMID:21605352

  4. Trabeculotomy combined with phacoemulsification and implantation of an intraocular lens for the treatment of primary open-angle glaucoma and coexisting cataract.

    PubMed

    Tanihara, H; Honjo, M; Inatani, M; Honda, Y; Ogino, N; Ueno, S; Negi, A; Ichioka, H; Mizoguchi, T; Matsumura, M; Nagata, M

    1997-10-01

    The authors previously reported the usefulness of trabeculotomy ab externo for the treatment of primary open-angle glaucoma in adult patients. In an attempt to elucidate the long-term risk-to-benefit ratio of this surgical modality in combination with cataract surgery, the authors conducted a retrospective study of the surgical effects and complications of a triple procedure: phacoemulsification, implantation (of an intraocular lens), and trabeculotomy (PIT). The authors conducted a retrospective study of patients treated with PIT at multiple hospitals. Intraocular pressure (IOP) and visual function data were obtained from patients after PIT as an initial surgical treatment in cases where antiglaucoma medications failed to resolve uncontrolled IOP (higher than 21 mm Hg). Included in this study were 96 eyes of 64 patients with primary open-angle glaucoma and coexisting cataract. The mean follow-up period was 22.6 +/- 14.7 months (range 3-56 months). In 94 (98%) of the 96 eyes, the IOP was well controlled, having achieved a level of 21 mm Hg or lower at the final examinations. The mean preoperative IOP of the 33 eyes that underwent the triple procedure using a single flap method (PIT-I) was 24.3 +/- 3.9 mm Hg, with an average of 2.1 +/- 1.1 medications. At the final examinations, the mean IOP had dropped to 16.0 +/- 1.2 mm Hg, with an average of 1.2 +/- 1.2 medications. The mean preoperative IOP of the 63 eyes that underwent the triple procedure using a double flap method (PIT-II) was 26.2 +/- 6.2 mm Hg, with an average of 1.9 +/- 1.2 medications. At the final examination, the mean IOP for this group was 15.6 +/- 2.9 mm Hg, with an average of 1.0 +/- 0.9 medications. The long-term results from this multicenter study showed that the triple procedure, PIT, can be useful and effective as an initial surgical treatment for open-angle glaucoma in glaucoma patients with coexisting cataract.

  5. Treatment carryover impacts on effectiveness of intraocular pressure lowering agents, estimated by a discrete event simulation model.

    PubMed

    Denis, P; Le Pen, C; Umuhire, D; Berdeaux, G

    2008-01-01

    To compare the effectiveness of two treatment sequences, latanoprost-latanoprost timolol fixed combination (L-LT) versus travoprost-travoprost timolol fixed combination (T-TT), in the treatment of open-angle glaucoma (OAG) or ocular hypertension (OHT). A discrete event simulation (DES) model was constructed. Patients with either OAG or OHT were treated first-line with a prostaglandin, either latanoprost or travoprost. In case of treatment failure, patients were switched to the specific prostaglandin-timolol sequence LT or TT. Failure was defined as intraocular pressure higher than or equal to 18 mmHg at two visits. Time to failure was estimated from two randomized clinical trials. Log-rank tests were computed. Linear functions after log-log transformation were used to model time to failure. The time horizon of the model was 60 months. Outcomes included treatment failure and disease progression. Sensitivity analyses were performed. Latanoprost treatment resulted in more treatment failures than travoprost (p<0.01), and LT more than TT (p<0.01). At 60 months, the probability of starting a third treatment line was 39.2% with L-LT versus 29.9% with T-TT. On average, L-LT patients developed 0.55 new visual field defects versus 0.48 for T-TT patients. The probability of no disease progression at 60 months was 61.4% with L-LT and 65.5% with T-TT. Based on randomized clinical trial results and using a DES model, the T-TT sequence was more effective at avoiding starting a third line treatment than the L-LT sequence. T-TT treated patients developed less glaucoma progression.

  6. Verification of the Robin and Graham classification system of hip disease in cerebral palsy using three-dimensional computed tomography.

    PubMed

    Gose, Shinichi; Sakai, Takashi; Shibata, Toru; Akiyama, Keisuke; Yoshikawa, Hideki; Sugamoto, Kazuomi

    2011-12-01

    We evaluated the validity of the Robin and Graham classification system of hip disease in cerebral palsy (CP) using three-dimensional computed tomography in young people with CP. A total of 91 hips in 91 consecutive children with bilateral spastic CP (57 males, 34 females; nine classified at Gross Motor Function Classification System level II, 42 at level III, 32 at level IV, and eight at level V; mean age 5 y 2 mo, SD 11 mo; range 2-6 y) were investigated retrospectively using anteroposterior plain radiographs and three-dimensional computed tomography (3D-CT) of the hip. The migration percentage was calculated on plain radiographs and all participants were classified into four groups according to migration percentage: grade II, migration percentage ≥ 10% but ≤ 15%, (four hips), grade III, migration percentage >15% but ≤ 30%, (20 hips); grade IV, migration percentage >30% but <100%, (63 hips); and grade V, migration percentage ≥ 100%, (four hips). The lateral opening angle and the sagittal inclination angle of the acetabulum, the neck-shaft angle, and the femoral anteversion of the femur were measured on 3D-CT. The three-dimensional quantitative evaluation indicated that there were significant differences in the lateral opening angle and the neck-shaft angle between the four groups (Kruskal-Wallis test, p ≤ 0.001). This three-dimensional evaluation supports the validation of the Robin and Graham classification system for hip disease in 2- to 7-year-olds with CP. © The Authors. Developmental Medicine & Child Neurology © 2011 Mac Keith Press.

  7. Comparison of gonioscopy and anterior segment ocular coherence tomography in detecting angle closure in different quadrants of the anterior chamber angle.

    PubMed

    Sakata, Lisandro M; Lavanya, Raghavan; Friedman, David S; Aung, Han T; Gao, Hong; Kumar, Rajesh S; Foster, Paul J; Aung, Tin

    2008-05-01

    To compare the performance of gonioscopy and anterior segment (AS) optical coherence tomography (OCT) in detecting angle closure in the different quadrants of the anterior chamber angle (ACA). Cross-sectional observational study. Five hundred two consecutive subjects more than 50 years of age with no previous ophthalmic problems recruited from a community clinic in Singapore. All subjects underwent gonioscopy and AS OCT imaging in the dark. Using gonioscopy, the ACA was graded using the Scheie system by a single examiner masked to AS OCT findings. The ACA in a particular quadrant was classified as closed if the posterior trabecular meshwork could not be seen on gonioscopy. A closed ACA on AS OCT imaging was defined by the presence of any contact between the iris and angle wall anterior to the scleral spur. After excluding eyes with poor image quality, a total of 423 right eyes were included in the analysis. A closed angle in at least 1 quadrant was observed in 59% of the eyes by AS OCT and in 33% of the eyes by gonioscopy (P<0.001), with fair agreement between the two methods (kappa = 0.40). The frequency of closed angles by AS OCT and gonioscopy were 48% versus 29% superiorly, 43% versus 22% inferiorly, 18% versus 14% nasally, and 12% versus 20% temporally, respectively. Of the 119 of 1692 quadrants that were closed on gonioscopy but open on AS OCT, a steep iris profile was present in 61 (51%) of 119 quadrants on AS OCT, and of the 276 of 1692 quadrants that were open on gonioscopy but closed on AS OCT, 196 (71%) of 276 quadrants showed short iridoangle contact on AS OCT. The highest rates of closed angles on gonioscopy and AS OCT images were observed in the superior quadrant. Anterior segment OCT tended to detect more closed ACAs than gonioscopy, particularly in the superior and inferior quadrants. Variations in the iris profile and level of iridoangle contact also may explain some of the differences seen between gonioscopy and AS OCT.

  8. Disruption of spatial organization and interjoint coordination in Parkinson's disease, progressive supranuclear palsy, and multiple system atrophy.

    PubMed

    Leiguarda, R; Merello, M; Balej, J; Starkstein, S; Nogues, M; Marsden, C D

    2000-07-01

    Patients with basal ganglia diseases may exhibit ideomotor apraxia. To define the nature of the impairment of the action production system, we studied a repetitive gesture of slicing bread by three-dimensional computergraphic analysis in eight nondemented patients with Parkinson's disease in the "on" state, five with progressive supranuclear palsy and four with multiple system atrophy. Two patients with Parkinson's disease and two with progressive supranuclear palsy showed ideomotor apraxia for transitive movements on standard testing. A Selspott II system was used for kinematic analysis of wrist trajectories and angular motions of the shoulder and elbow joints. Patients with Parkinson's disease, progressive supranuclear palsy, and even some with multiple system atrophy exhibited kinematic deficits in the spatial precision of movement and velocity-curvature relationships; in addition, they failed to maintain proper angle/angle relationships and to apportion their relative joint amplitudes normally. Spatial disruption of wrist trajectories was more severe in patients with ideomotor apraxia. We posit that the basal ganglia are part of the parallel parieto-frontal circuits devoted to sensorimotor integration for object-oriented behavior. The severity and characteristics of spatial abnormalities of a transitive movement would therefore depend on the location and distribution of the pathologic process within these circuits.

  9. EMIIM Wetting Properties & Their Effect on Electrospray Thruster Design

    DTIC Science & Technology

    2012-03-01

    tension and contact or “wetting" angle formed when a liquid droplet comes in contact with a solid surface. Ideally this angle is a function of the...3 3 Picture of a Taylor cone formed at AFRL, note bubbles present. . . . . . . 3 4 Titanium electrode grids in use at AFRL...cone formed using an internally wetted emitter and the ionic liquid BMI-BG4 is shown in Figure 3.[7] Emitters are precisely aligned with openings

  10. 21 CFR 872.3730 - Pantograph.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... and, as the patient's mouth opens, the pen records on graph paper the angle between the upper and the lower jaw. (b) Classification. Class I (general controls). The device is exempt from the premarket...

  11. Genetics Home Reference: early-onset glaucoma

    MedlinePlus

    ... called a syndrome. If glaucoma appears before the age of 5 without other associated abnormalities, it is called primary congenital glaucoma. Other individuals experience early onset of primary open-angle glaucoma, the most ...

  12. Glaucoma, Open-Angle

    MedlinePlus

    ... is to “conduct and support research, training, health information dissemination, and other programs with respect to blinding eye ... Media Policies and Other Important Links NEI Employee Emergency Information NEI Intranet (Employees Only) *PDF files require ...

  13. Glaucoma in Asian Populations

    MedlinePlus

    ... in their Asian counterparts. Normal Tension Glaucoma affects Japanese Japanese populations, however, have a substantially higher incidence of ... factor for open angle glaucoma). In fact, a Japanese study found NTG accounted for 92 percent of ...

  14. Peeling-angle dependence of the stick-slip instability during adhesive tape peeling.

    PubMed

    Dalbe, Marie-Julie; Santucci, Stéphane; Vanel, Loïc; Cortet, Pierre-Philippe

    2014-12-28

    The influence of peeling angle on the dynamics observed during the stick-slip peeling of an adhesive tape has been investigated. This study relies on a new experimental setup for peeling at a constant driving velocity while keeping constant the peeling angle and peeled tape length. The thresholds of the instability are shown to be associated with a subcritical bifurcation and bistability of the system. The velocity onset of the instability is moreover revealed to strongly depend on the peeling angle. This could be the consequence of peeling angle dependance of either the fracture energy of the adhesive-substrate joint or the effective stiffness at play between the peeling front and the point at which the peeling is enforced. The shape of the peeling front velocity fluctuations is finally shown to progressively change from typical stick-slip relaxation oscillations to nearly sinusoidal oscillations as the peeling angle is increased. We suggest that this transition might be controlled by inertial effects possibly associated with the propagation of the peeling force fluctuations through elongation waves in the peeled tape.

  15. Gyre formation within embayments of a large lake (Lake Geneva, Switzerland)

    NASA Astrophysics Data System (ADS)

    Razmi, A.; Barry, D.; Bouffard, D.; Le Dantec, N.; Lemmin, U.; Wuest, A.

    2013-12-01

    Numerical simulations were carried out to examine gyre formation within open, wide lacustrine embayments. The present study was motivated by observed differences in gyre formation within two open and wide embayments (located at Vidy and Morges in Lake Geneva, Switzerland). These two embayments are located within about 3 km of each other on the northern shore of Lake Geneva, and are subjected to similar pelagic currents. Vidy is deeper and has a greater aspect ratio than Morges. The flow field in the embayments was modeled using a previously validated 3D hydrodynamic model (Delft3D-FLOW). The model solved the Reynolds-Averaged Navier-Stokes equations, combined with a k-ɛ turbulence closure in σ (lakebed-following) coordinates. Our study focused on the influence of the embayment geometry on the (uniform) longshore (pelagic) current, specifically the occurrence and magnitude of circulation within the embayment. We built a set of numerical experiments using synthetic embayments, and systematically examined embayment geometry, thereby capturing the differences between the Vidy and Morges embayments. The numerical experiments considered single rectilinear embayments with different aspect ratios (i.e., 1-6), depth, shore-parallel flow rates, and embayment corner angle between 0°-50°. The circulation magnitude changes abruptly for an angle of about 40°. Embayments with angles greater than 40° have much greater circulation then those with lesser angles, other factors remaining the same. Of the factors considered (i.e., aspect ratio, offshore current velocity, corner angle, bottom slope, and viscosity), bottom slope and the viscosity have almost no impact on embayment circulation. For uniform offshore current patterns, gyres form in embayments with large aspect ratios (up to ~3). For the Vidy and Morges embayments, the results showed that gyre formation is more likely in Morges due to its smaller aspect ratio, a finding that is supported by field data gathered in drifter studies. For example, simultaneous drifter releases in 2011 showed parallel-to-shore currents in the Vidy embayment and a gyre in Morges. KEYWORDS: Hydrodynamics; Open Embayment; Flow Separation; Gyre; Topography; Lake Geneva.

  16. Apparatus For Laminating Segmented Core For Electric Machine

    DOEpatents

    Lawrence, Robert Anthony; Stabel, Gerald R

    2003-06-17

    A segmented core for an electric machine includes segments stamped from coated electric steel. The segments each have a first end, a second end, and winding openings. A predetermined number of segments are placed end-to-end to form layers. The layers are stacked such that each of the layers is staggered from adjacent layers by a predetermined rotation angle. The winding openings of each of the layers are in vertical alignment with the winding openings of the adjacent layers. The stack of layers is secured to form the segmented core.

  17. Hurricane Katrina

    Atmospheric Science Data Center

    2014-05-15

    ... Katrina is one of the most powerful and destructive storms on record for the Atlantic Basin. The animation progresses from ... tops" are also characteristic of strong and rapidly growing storms. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth ...

  18. Mapping a gene for adult-onset primary open-angle glaucoma to chromosome 3q

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wirtz, M.K.; Samples, J.R.; Kramer, P.L.

    1997-02-01

    Glaucoma is the third-leading cause of blindness in the world, affecting >13.5 million people. Adult-on-set primary open-angle glaucoma (POAG) is the most common form of glaucoma in the United States. We present a family in which adult-onset POAG is inherited as an autosomal dominant trait. Twelve affected family members were identified from 44 at-risk individuals. The disease-causing gene was mapped to chromosome 3q21-24, with analysis of recombinant haplotypes suggesting a total inclusion region of 11.1 cM between markers D3S3637 and D3S1744. This is the first report of mapping of an adult-onset POAG gene to chromosome 3q, gene symbol GLC1C. 57more » refs., 3 figs., 3 tabs.« less

  19. A Relationship Between Constraint and the Critical Crack Tip Opening Angle

    NASA Technical Reports Server (NTRS)

    Johnston, William M.; James, Mark A.

    2009-01-01

    Of the various approaches used to model and predict fracture, the Crack Tip Opening Angle (CTOA) fracture criterion has been successfully used for a wide range of two-dimensional thin-sheet and thin plate applications. As thicker structure is considered, modeling the full three-dimensional fracture process will become essential. This paper investigates relationships between the local CTOA evaluated along a three-dimensional crack front and the corresponding local constraint. Previously reported tunneling crack front shapes were measured during fracture by pausing each test and fatigue cycling the specimens to mark the crack surface. Finite element analyses were run to model the tunneling shape during fracture, with the analysis loading conditions duplicating those tests. The results show an inverse relationship between the critical fracture value and constraint which is valid both before maximum load and after maximum load.

  20. Blindness following bleb-related infection in open angle glaucoma.

    PubMed

    Yamada, Hiroki; Sawada, Akira; Kuwayama, Yasuaki; Yamamoto, Tetsuya

    2014-11-01

    To estimate the risk of blindness following bleb-related infection after trabeculectomy with mitomycin C in open angle glaucoma, utilizing data obtained from two prospective multicenter studies. The incidence of bleb-related infection in open angle glaucoma after the first or second glaucoma surgery was calculated using a Kaplan-Meier analysis and data from the Collaborative Bleb-related Infection Incidence and Treatment Study (CBIITS). The rate of blindness following bleb-related infection was calculated using data from the Japan Glaucoma Society Survey of Bleb-related Infection (JGSSBI). Finally, the rate of blindness following bleb-related infection after filtering surgery was estimated based on the above two data sets. Blindness was defined as an eye with a visual acuity of 0.04 or less. The incidences of development of bleb-related infection at 5 years were 2.6 ± 0.7 % (calculated cumulative incidence ± standard error) for all infections and 0.9 ± 0.4 % for endophthalmitis in all cases in the CBIITS data. The rates of blindness in the JGSSBI data were 14 % for the total cases with bleb-related infection and 30 % for the endophthalmitis subgroup. The rate of blindness developing within 5 years following trabeculectomy was estimated to be approximately 0.24-0.36 %. The rate of blindness following bleb-related infection within 5 years after trabeculectomy is considerable and thus careful consideration must be given to the indication for trabeculectomy and the selection of surgical techniques.

  1. Effect of open hole on tensile failure properties of 2D triaxial braided textile composites and tape equivalents

    NASA Technical Reports Server (NTRS)

    Norman, Timothy L.; Anglin, Colin; Gaskin, David; Patrick, Mike

    1995-01-01

    The unnotched and notched (open hole) tensile strength and failure mechanisms of two-dimensional (2D) triaxial braided composites were examined. The effect of notch size and notch position were investigated. Damage initiation and propagation in notched and unnotched coupons were also examined. Theory developed to predict the normal stress distribution near an open hole and failure for tape laminated composites was evaluated for its applicability to triaxial braided textile composite materials. Four fiber architectures were considered with different combinations of braid angle, longitudinal and braider yam size, and percentage of longitudinal yarns. Tape laminates equivalent to textile composites were also constructed for comparison. Unnotched tape equivalents were stronger than braided textiles but exhibited greater notch sensitivity. Notched textiles and tape equivalents have roughly the same strength at large notch sizes. Two common damage mechanisms were found: braider yams cracking and near notch longitudinal yarn splitting. Cracking was found to initiate in braider yarns in unnotched and notched coupons, and propagate in the direction of the braider yarns until failure. Longitudinal yarn splitting occurred in three of four architectures that were longitudinally fiber dominated. Damage initiation stress decreased with increasing braid angle. No significant differences in prediction of near notch stress between measured and predicted stress were weak for textiles with large braid angle. Notch strength could not be predicted using existing anisotropic theory for braided textiles due to their insensitivity to notch.

  2. The molecular mechanism of plant gravitropism.

    PubMed

    Wu, Di; Huang, Lin-zhou; Gao, Jin; Wang, Yong-hong

    2016-07-20

    Gravity is an important environmental factor that regulates plant growth and morphogenesis. In response to gravity stimulus, plants can set the optimum angle between the organs and the gravity vector. Plant gravitropism is divided into four sequential steps, including gravity perception, signal transduction, asymmetrical distribution of auxin, and organ curvature. In recent years, large numbers of mutants with defective gravitropism have been identified and genes involved in the regulation of gravitropism have been functionally characterized. In particular, progress has been achieved on elucidating the molecular mechanisms of gravity perception and asymmetrical distribution of auxin. As one of the most important strategies for plant to adapt environmental changes, gravitropism is also involved in the regulation of rice plant architecture and grain yield through modulating rice tiller angle. Therefore, the investigation of plant gravitropism not only contributes to decipher the regulatory mechanisms of plant growth and development, but also helps to guide the genetic improvement of crop architecture. However, the molecular mechanisms and regulatory network of gravitropism remain to be elusive. In this review, we focus on recent progress on elucidating molecular mechanisms underlying gravitropism and its involvement in regulating rice tiller angle, which is an important agronomic trait that determines rice plant architecture and thus grain yields.

  3. Intersecting flavor branes

    NASA Astrophysics Data System (ADS)

    Pomoni, Elli; Rastelli, Leonardo

    2012-10-01

    We consider an instance of the AdS/CFT duality where the bulk theory contains an open string tachyon, and study the instability from the viewpoint of the boundary field theory. We focus on the specific example of the AdS5 × S 5 background with two probe D7 branes intersecting at general angles. For generic angles supersymmetry is completely broken and there is an open string tachyon between the branes. The field theory action for this system is obtained by coupling to {N}=4 super Yang-Mills two {N}=2 hyper multiplets in the fundamental representation of the SU( N) gauge group, but with different choices of embedding of the two {N}=2 subalgebras into {N}=4 . On the field theory side we find a one-loop Coleman-Weinberg instability in the effective potential for the fundamental scalars. We identify a mesonic operator as the dual of the open string tachyon. By AdS/CFT, we predict the tachyon mass for small 't Hooft coupling (large bulk curvature) and confirm that it violates the AdS stability bound.

  4. A new technique for quantifying symmetry and opening angles in quartz c-axis pole figures: Implications for interpreting the kinematic and thermal properties of rocks

    NASA Astrophysics Data System (ADS)

    Hunter, N. J. R.; Weinberg, R. F.; Wilson, C. J. L.; Law, R. D.

    2018-07-01

    Variations in flow kinematics influence the type of crystallographic preferred orientations (CPOs) in plastically deformed quartz, yet we currently lack a robust means of quantifying the diagnostic symmetries that develop in the c-axis (0001) pole figure. In this contribution, we demonstrate how the symmetry of common c-axis topologies may be quantified by analysing the intensity distribution across a line transect of the pole figure margin. A symmetry value (S) measures the relative difference in intensities between marginal girdle maxima in the pole figure, and thus the degree to which the pole figure defines orthorhombic or monoclinic end member symmetries. This provides a semi-quantitative depiction of whether the rocks underwent coaxial or non-coaxial flow, respectively, and may subsequently be used to quantify other topological properties, such as the opening angle of girdle maxima. The open source Matlab® toolbox MTEX is used to quantify pole figure symmetries in quartzite samples from the Main Central Thrust (NW Himalaya) and the Moine Thrust (NW Scotland).

  5. Broadband and polarization reflectors in the lookdown, Selene vomer

    PubMed Central

    Zhao, Shulei; Brady, Parrish Clawson; Gao, Meng; Etheredge, Robert Ian; Kattawar, George W.; Cummings, Molly E.

    2015-01-01

    Predator evasion in the open ocean is difficult because there are no objects to hide behind. The silvery surface of fish plays an important role in open water camouflage. Various models have been proposed to account for the broadband reflectance by the fish skin that involve one-dimensional variations in the arrangement of guanine crystal reflectors, yet the three-dimensional organization of these guanine platelets have not been well characterized. Here, we report the three-dimensional organization and the optical properties of integumentary guanine platelets in a silvery marine fish, the lookdown (Selene vomer). Our structural analysis and computational modelling show that stacks of guanine platelets with random yaw angles in the fish skin produce broadband reflectance via colour mixing. Optical axes of the guanine platelets and the collagen layer are aligned closely and provide bulk birefringence properties that influence the polarization reflectance by the skin. These data demonstrate how the lookdown preserves or alters polarization states at different incident polarization angles. These optical properties resulted from the organization of these guanine platelets and the collagen layer may have implications for open ocean camouflage in varying light fields. PMID:25673301

  6. Si Lattice, Avogadro Constant, and X- and Gamma-Ray Measurements: Contributions by R.D. Deslattes

    NASA Astrophysics Data System (ADS)

    Kessler, Jr.

    2002-04-01

    The achievement of x-ray interferometry in 1965 opened the possibility of more accurately measuring the lattice spacing of a diffraction crystal on a scale directly tied to the SI system of units. The road from the possible to reality required moving objects and measuring translations with sub-atomic accuracy. The improved crystal lattice spacing determinations had a significant impact on two fundamental measurement areas: 1) the amount of substance (the mole and the associated Avogadro Constant), and 2) short wavelengths (the x- and gamma-ray regions). Progress in both areas required additional metrological advances: density and isotopic abundance measurements are needed for the Avogadro constant and small angle measurements are required for the determination of short wavelengths. The x- and gamma-ray measurements have led to more accurate wavelength standards and neutron binding energy measurements that connect gamma-ray measurements to precision atomic mass measurements, particularly the neutron mass. Richard D. Deslattes devoted much of his scientific career to this measurement program. His outstanding contributions and insights will be reviewed.

  7. A new generation scanning system for the high-speed analysis of nuclear emulsions

    NASA Astrophysics Data System (ADS)

    Alexandrov, A.; Buonaura, A.; Consiglio, L.; D'Ambrosio, N.; De Lellis, G.; Di Crescenzo, A.; Galati, G.; Lauria, A.; Montesi, M. C.; Tioukov, V.; Vladymyrov, M.

    2016-06-01

    The development of automatic scanning systems was a fundamental issue for large scale neutrino detectors exploiting nuclear emulsions as particle trackers. Such systems speed up significantly the event analysis in emulsion, allowing the feasibility of experiments with unprecedented statistics. In the early 1990s, R&D programs were carried out by Japanese and European laboratories leading to automatic scanning systems more and more efficient. The recent progress in the technology of digital signal processing and of image acquisition allows the fulfillment of new systems with higher performances. In this paper we report the description and the performance of a new generation scanning system able to operate at the record speed of 84 cm2/hour and based on the Large Angle Scanning System for OPERA (LASSO) software infrastructure developed by the Naples scanning group. Such improvement, reduces the scanning time by a factor 4 with respect to the available systems, allowing the readout of huge amount of nuclear emulsions in reasonable time. This opens new perspectives for the employment of such detectors in a wider variety of applications.

  8. Recent advances in superhydrophobic surfaces and their relevance to biology and medicine.

    PubMed

    Ciasca, G; Papi, M; Businaro, L; Campi, G; Ortolani, M; Palmieri, V; Cedola, A; De Ninno, A; Gerardino, A; Maulucci, G; De Spirito, M

    2016-02-04

    By mimicking naturally occurring superhydrophobic surfaces, scientists can now realize artificial surfaces on which droplets of a few microliters of water are forced to assume an almost spherical shape and an extremely high contact angle. In recent decades, these surfaces have attracted much attention due to their technological applications for anti-wetting and self-cleaning materials. Very recently, researchers have shifted their interest to investigate whether superhydrophobic surfaces can be exploited to study biological systems. This research effort has stimulated the design and realization of new devices that allow us to actively organize, visualize and manipulate matter at both the microscale and nanoscale levels. Such precise control opens up wide applications in biomedicine, as it allows us to directly manipulate objects at the typical length scale of cells and macromolecules. This progress report focuses on recent biological and medical applications of superhydrophobicity. Particular regard is paid to those applications that involve the detection, manipulation and study of extremely small quantities of molecules, and to those that allow high throughput cell and biomaterial screening.

  9. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Gang; Kong, Lingping; Gong, Jue

    Bond length and bond angle exhibited by valence electrons is essential to the core of chemistry. Using lead-based organic–inorganic perovskite compounds as an exploratory platform, it is demonstrated that the modulation of valence electrons by compression can lead to discovery of new properties of known compounds. Yet, despite its unprecedented progress, further efficiency boost of lead-based organic–inorganic perovskite solar cells is hampered by their wider bandgap than the optimum value according to the Shockley–Queisser limit. By modulating the valence electron wavefunction with modest hydraulic pressure up to 2.1 GPa, the optimized bandgap for single-junction solar cells in lead-based perovskites, formore » the first time, is achieved by narrowing the bandgap of formamidinium lead triiodide (HC(NH 2) 2PbI 3) from 1.489 to 1.337 eV. Strikingly, such bandgap narrowing is partially retained after the release of pressure to ambient, and the bandgap narrowing is also accompanied with double-prolonged carrier lifetime. With First-principles simulation, this work opens a new dimension in basic chemical understanding of structural photonics and electronics and paves an alternative pathway toward better photovoltaic materials-by-design.« less

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Gang; Kong, Lingping; Gong, Jue

    Bond length and bond angle exhibited by valence electrons is essential to the core of chemistry. Using lead-based organic–inorganic perovskite compounds as an exploratory platform, it is demonstrated that the modulation of valence electrons by compression can lead to discovery of new properties of known compounds. Yet, despite its unprecedented progress, further efficiency boost of lead-based organic–inorganic perovskite solar cells is hampered by their wider bandgap than the optimum value according to the Shockley–Queisser limit. By modulating the valence electron wavefunction with modest hydraulic pressure up to 2.1 GPa, the optimized bandgap for single-junction solar cells in lead-based perovskites, formore » the first time, is achieved by narrowing the bandgap of formamidinium lead triiodide (HC(NH2)2PbI3) from 1.489 to 1.337 eV. Strikingly, such bandgap narrowing is partially retained after the release of pressure to ambient, and the bandgap narrowing is also accompanied with double-prolonged carrier lifetime. With First-principles simulation, this work opens a new dimension in basic chemical understanding of structural photonics and electronics and paves an alternative pathway toward better photovoltaic materials-by-design.« less

  11. Gyrokinetic continuum simulations of turbulence in the Texas Helimak

    NASA Astrophysics Data System (ADS)

    Bernard, T. N.; Shi, E. L.; Hammett, G. W.; Hakim, A.; Taylor, E. I.

    2017-10-01

    We have used the Gkeyll code to perform 3x-2v full-f gyrokinetic continuum simulations of electrostatic plasma turbulence in the Texas Helimak. The Helimak is an open field-line experiment with magnetic curvature and shear. It is useful for validating numerical codes due to its extensive diagnostics and simple, helical geometry, which is similar to the scrape-off layer region of tokamaks. Interchange and drift-wave modes are the main turbulence mechanisms in the device, and potential biasing is applied to study the effect of velocity shear on turbulence reduction. With Gkeyll, we varied field-line pitch angle and simulated biased and unbiased cases to study different turbulent regimes and turbulence reduction. These are the first kinetic simulations of the Helimak and resulting plasma profiles agree fairly well with experimental data. This research demonstrates Gkeyll's progress towards 5D simulations of the SOL region of fusion devices. Supported by the U.S. DOE SCGSR program under contract DE-SC0014664, the Max-Planck/Princeton Center for Plasma Physics, the SciDAC Center for the Study of Plasma Microturbulence, and DOE contract DE-AC02-09CH11466.

  12. Genome-wide analysis of multiethnic cohorts identifies new loci influencing intraocular pressure and susceptibility to glaucoma

    PubMed Central

    Vitart, Veronique; Nag, Abhishek; Hewitt, Alex W; Höhn, René; Venturini, Cristina; Mirshahi, Alireza; Ramdas, Wishal D.; Thorleifsson, Gudmar; Vithana, Eranga; Khor, Chiea-Chuen; Stefansson, Arni B; Liao, Jiemin; Haines, Jonathan L; Amin, Najaf; Wang, Ya Xing; Wild, Philipp S; Ozel, Ayse B; Li, Jun Z; Fleck, Brian W; Zeller, Tanja; Staffieri, Sandra E; Teo, Yik-Ying; Cuellar-Partida, Gabriel; Luo, Xiaoyan; Allingham, R Rand; Richards, Julia E; Senft, Andrea; Karssen, Lennart C; Zheng, Yingfeng; Bellenguez, Céline; Xu, Liang; Iglesias, Adriana I; Wilson, James F; Kang, Jae H; van Leeuwen, Elisabeth M; Jonsson, Vesteinn; Thorsteinsdottir, Unnur; Despriet, Dominiek D.G.; Ennis, Sarah; Moroi, Sayoko E; Martin, Nicholas G; Jansonius, Nomdo M; Yazar, Seyhan; Tai, E-Shyong; Amouyel, Philippe; Kirwan, James; van Koolwijk, Leonieke M.E.; Hauser, Michael A; Jonasson, Fridbert; Leo, Paul; Loomis, Stephanie J; Fogarty, Rhys; Rivadeneira, Fernando; Kearns, Lisa; Lackner, Karl J; de Jong, Paulus T.V.M.; Simpson, Claire L; Pennell, Craig E; Oostra, Ben A; Uitterlinden, André G; Saw, Seang-Mei; Lotery, Andrew J; Bailey-Wilson, Joan E; Hofman, Albert; Vingerling, Johannes R; Maubaret, Cécilia; Pfeiffer, Norbert; Wolfs, Roger C.W.; Lemij, Hans G; Young, Terri L; Pasquale, Louis R; Delcourt, Cécile; Spector, Timothy D; Klaver, Caroline C.W.; Small, Kerrin S; Burdon, Kathryn P; Stefansson, Kari; Wong, Tien-Yin; Viswanathan, Ananth; Mackey, David A; Craig, Jamie E; Wiggs, Janey L; van Duijn, Cornelia M; Hammond, Christopher J; Aung, Tin

    2014-01-01

    Elevated intraocular pressure (IOP) is an important risk factor in developing glaucoma and IOP variability may herald glaucomatous development or progression. We report the results of a genome-wide association study meta-analysis of 18 population cohorts from the International Glaucoma Genetics Consortium (IGGC), comprising 35,296 multiethnic participants for IOP. We confirm genetic association of known loci for IOP and primary open angle glaucoma (POAG) and identify four new IOP loci located on chromosome 3q25.31 within the FNDC3B gene (p=4.19×10−08 for rs6445055), two on chromosome 9 (p=2.80×10−11 for rs2472493 near ABCA1 and p=6.39×10−11 for rs8176693 within ABO) and one on chromosome 11p11.2 (best p=1.04×10−11 for rs747782). Separate meta-analyses of four independent POAG cohorts, totaling 4,284 cases and 95,560 controls, show that three of these IOP loci are also associated with POAG. PMID:25173106

  13. Comparing approaches to screening for angle closure in older Chinese adults

    PubMed Central

    Andrews, J; Chang, D S; Jiang, Y; He, M; Foster, P J; Munoz, B; Kashiwagi, K; Friedman, D S

    2012-01-01

    Aims Primary angle-closure glaucoma is expected to account for nearly 50% of bilateral glaucoma blindness by 2020. This study was conducted to assess the performance of the scanning peripheral anterior chamber depth analyzer (SPAC) and limbal anterior chamber depth (LACD) as screening methods for angle closure. Methods This study assessed two clinical populations to compare SPAC, LACD, and gonioscopy: the Zhongshan Angle-closure Prevention Trial, from which 370 patients were eligible as closed-angle participants and the Liwan Eye Study, from which 72 patients were selected as open-angle controls. Eligible participants were assessed by SPAC, LACD, and gonioscopy. Results Angle status was defined by gonioscopy. Area under the receiver operating characteristic curve (AUROC) for SPAC was 0.92 (0.89–0.95) whereas AUROC for LACD was 0.94 (0.92–0.97). Using conventional cutoff points, sensitivity/specificity was 93.0%/70.8% for SPAC and 94.1%/87.5% for LACD. Sequential testing using both SPAC and LACD increased the specificity to 94.4% and decreased the sensitivity to 87.0%. Conclusion SPAC has significantly lower specificity than LACD measurement using conventional cutoffs but interpretation of the findings can be performed by modestly trained personnel. PMID:21997356

  14. Serial Derotational Casting in Idiopathic and Non-Idiopathic Progressive Early-Onset Scoliosis.

    PubMed

    Gussous, Yazeed M; Tarima, Sergey; Zhao, Shi; Khan, Safdar; Caudill, Angela; Sturm, Peter; Hammerberg, Kim W

    2015-05-01

    Serial derotational casting has been used as a definitive treatment or as delaying strategy in progressive idiopathic (IS) and non-idiopathic (NIS) early-onset scoliosis (EOS). Retrospective chart and radiographic review of patients who underwent serial casting for progressive EOS between 2005 and 2012 at a single institution. A total of 74 consecutive patients entered serial cast treatment. Twenty-eight were currently being casted, 30 completed cast treatment and were converted to thoracolumbosacral orthosis (TLSO), 9 were treated surgically, 6 were lost to follow-up, and 1 had no further treatment. The researchers diagnosed IS in 41 patients; 33 had NIS. At presentation the IS group had an average Cobb angle (CA) of 49° and a rib vertebral angle difference (RVAD) of 37°. The NIS group had a CA of 51° (p = .69) and RVAD of 37° (p = .94). In patients currently being casted, 19 IS patients had a decreased CA, from 47° to 27°. The 9 NIS patients had a decreased CA, from 62° to 57° (p = .0002). Cobb angle improvement was significantly better in IS (p = .0005). In the TLSO group the 17 IS patients had a decreased average CA, from 46° to 18°, after serial casting and the 13 NIS patients decreased CA from 42° to 32°. Patients with IS had better improvement in CA than the NIS group (p < .001). At last follow-up, this was reduced to 11° in the IS group and maintained at 32° in the NIS. In the IS group, 5 of 41 patients were converted to growth constructs, and 4 of 26 in the NIS group. Casting initiated before age 2 years yielded better curve correction for IS (p < .01) compared with NIS. Progressive idiopathic scoliosis patients had better curve correction with casting than NIS patients. Casting in IS patients before age 24 months yielded better curve correction. Patients who required surgery had a higher age and Cobb angle at presentation than those who transitioned to a TLSO. The surgical group was observed for a similar duration of time and there was no significant statistical difference. Although RVAD is a predictor of progression in infantile IS, it did not show a predictive value in the response to casting of either the IS or NIS groups. Copyright © 2015 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.

  15. Magnetic reconnection in 3D magnetosphere models: magnetic separators and open flux production

    NASA Astrophysics Data System (ADS)

    Glocer, A.; Dorelli, J.; Toth, G.; Komar, C. M.; Cassak, P.

    2014-12-01

    There are multiple competing definitions of magnetic reconnection in 3D (e.g., Hesse and Schindler [1988], Lau and Finn [1990], and Boozer [2002]). In this work we focus on separator reconnection. A magnetic separator can be understood as the 3D analogue of a 2D x line with a guide field, and is defined by the line corresponding to the intersection of the separatrix surfaces associated with the magnetic nulls. A separator in the magnetosphere represents the intersection of four distinct magnetic topologies: solar wind, closed, open connected to the northern hemisphere, and open connected to the southern hemisphere. The integral of the parallel electric field along the separator defines the rate of open flux production, and is one measure of the reconnection rate. We present three methods for locating magnetic separators and apply them to 3D resistive MHD simulations of the Earth's magnetosphere using the BATS-R-US code. The techniques for finding separators and determining the reconnection rate are insensitive to IMF clock angle and can in principle be applied to any magnetospheric model. The present work examines cases of high and low resistivity, for two clock angles. We also examine the separator during Flux Transfer Events (FTEs) and Kelvin-Helmholtz instability.

  16. Scoliosis in osteogenesis imperfecta caused by COL1A1/COL1A2 mutations - genotype-phenotype correlations and effect of bisphosphonate treatment.

    PubMed

    Sato, Atsuko; Ouellet, Jean; Muneta, Takeshi; Glorieux, Francis H; Rauch, Frank

    2016-05-01

    Bisphosphonates are widely used to treat children with osteogenesis imperfecta (OI), a bone fragility disorder that is most often caused by mutations in COL1A1 or COL1A2. However, it is unclear whether this treatment decreases the risk of developing scoliosis. We retrospectively evaluated spine radiographs and charts of 437 patients (227 female) with OI caused by mutations in COL1A1 or COL1A2 and compared the relationship between scoliosis, genotype and bisphosphonate treatment history. At the last follow-up (mean age 11.9 [SD: 5.9] years), 242 (55%) patients had scoliosis. The prevalence of scoliosis was highest in OI type III (89%), followed by OI type IV (61%) and OI type I (36%). Moderate to severe scoliosis (Cobb angle ≥25°) was rare in individuals with COL1A1 haploinsufficiency mutations but was present in about two fifth of patients with triple helical glycine substitutions or C-propeptide mutations. During the first 2 to 4years of bisphosphonate therapy, patients with OI type III had lower Cobb angle progression rates than before bisphosphonate treatment, whereas in OI types I and IV bisphosphonate treatment was not associated with a change in Cobb angle progression rates. At skeletal maturity, the prevalence of scoliosis (Cobb angle >10°) was similar in patients who had started bisphosphonate treatment early in life (before 5.0years of age) and in patients who had started therapy later (after the age of 10.0years) or had never received bisphosphonate therapy. Bisphosphonate treatment decreased progression rate of scoliosis in OI type III but there was no evidence of a positive effect on scoliosis in OI types I and IV. The prevalence of scoliosis at maturity was not influenced by the bisphosphonate treatment history in any OI type. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Evaluation of a Wedge on a Force Balance as a Flow Angle Probe

    DTIC Science & Technology

    1975-02-01

    pitot rake attached to the Captive Trajectory System (CTS), and (3) measurement of flow angles in the same region with a probe attached to the CTS...localized pressures. Although it was the characteristics of supersonic flow which led to this conclusion, and even though the wedge design was based...vary the open area from near zero to 10 percent. Suction through the porous walls is used to maximize flow uniformity and to develop supersonic flow

  18. Hot spots in the microwave sky

    NASA Technical Reports Server (NTRS)

    Vittorio, Nicola; Juszkiewicz, Roman

    1987-01-01

    Tha assumption that the cosmic background fluctuations can be approximated as a random Gaussian field implies specific predictions for the radiation temperature pattern. Using this assumption, the abundances and angular sizes are calculated for regions of various levels of brightness expected to appear in the sky. Different observational strategies are assessed in the context of these results. Calculations for both large-angle and small-angle anisotropy generated by scale-invariant fluctuations in a flat universe are presented. Also discussed are simple generalizations to open cosmological models.

  19. Electric Dipole-Magnetic Dipole Polarizability and Anapole Magnetizability of Hydrogen Peroxide as Functions of the HOOH Dihedral Angle.

    PubMed

    Pelloni, S; Provasi, P F; Pagola, G I; Ferraro, M B; Lazzeretti, P

    2017-12-07

    The trace of tensors that account for chiroptical response of the H 2 O 2 molecule is a function of the HO-OH dihedral angle. It vanishes at 0° and 180°, due to the presence of molecular symmetry planes, but also for values in the range 90-100° of this angle, in which the molecule is unquestionably chiral. Such an atypical effect is caused by counterbalancing contributions of diagonal tensor components with nearly maximal magnitude but opposite sign, determined by electron flow in open or closed helical paths, and associated with induced electric and magnetic dipole moments and anapole moments. For values of dihedral angle external to the 90-100° interval, the helical paths become smaller in size, thus reducing the amount of cancellation among diagonal components. Shrinking of helical paths determines the appearance of extremum values of tensor traces approximately at 50° and 140° dihedral angles.

  20. Studying at the Open University of the Netherlands, Developments 1984-1987.

    ERIC Educational Resources Information Center

    Boon, J.; van Enckevort, G.

    A study examined the success of the first three years of the Dutch Open University's operation by analyzing data pertaining to students' backgrounds and academic progress while enrolled in the open university. The fact that registered inquiries about the Dutch Open University rose from 120,000 during the summer and autumn of 1984 to more than…

  1. Pulsed-neutron monochromator

    DOEpatents

    Mook, H.A. Jr.

    1984-01-01

    In one aspect, the invention is an improved pulsed-neutron monochromator of the vibrated-crystal type. The monochromator is designed to provide neutron pulses which are characterized both by short duration and high density. A row of neutron-reflecting crystals is disposed in a neutron beam to reflect neutrons onto a common target. The crystals in the row define progressively larger neutron-scattering angles and are vibrated sequentially in descending order with respect to the size of their scattering angles, thus generating neutron pulses which arrive simultaneously at the target. Transducers are coupled to one end of the crystals to vibrate them in an essentially non-resonant mode. The transducers propagate transverse waves in the crystal which progress longitudinally therein. The waves are absorbed at the undriven ends of the crystals by damping material mounted thereon. In another aspect, the invention is a method for generating neutron pulses characterized by high intensity and short duration.

  2. Pulsed-neutron monochromator

    DOEpatents

    Mook, Jr., Herbert A.

    1985-01-01

    In one aspect, the invention is an improved pulsed-neutron monochromator of the vibrated-crystal type. The monochromator is designed to provide neutron pulses which are characterized both by short duration and high density. A row of neutron-reflecting crystals is disposed in a neutron beam to reflect neutrons onto a common target. The crystals in the row define progressively larger neutron-scattering angles and are vibrated sequentially in descending order with respect to the size of their scattering angles, thus generating neutron pulses which arrive simultaneously at the target. Transducers are coupled to one end of the crystals to vibrate them in an essentially non-resonant mode. The transducers propagate transverse waves in the crystal which progress longitudinally therein. The wave are absorbed at the undriven ends of the crystals by damping material mounted thereon. In another aspect, the invention is a method for generating neutron pulses characterized by high intensity and short duration.

  3. Experimental measurements of heat transfer coefficient in a partially/fully opened tilted cavity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chakroun, W.; Elsayed, M.M.; Al-Fahed, S.F.

    1997-11-01

    An experimental investigation was carried out to determine the heat transfer coefficient from a rectangular tilted cavity to the ambient due to the buoyancy driven flow in the cavity. The cavity is partially or fully open from one side. All the walls of the cavity are adiabatic except the wall facing the cavity opening which is heated at a constant heat flux. Air was used as the cavity fluid and the experiments were carried out at a flux Grashof number of 5.5 {times} 10{sup 8}. The tilt angle of the cavity, measured from the vertical direction, was changed between {minus}90more » deg to +90 deg in 15 deg increments. Also, geometries of aspect ratio (height-to-width of cavity) of 1.0, 0.5, and 0.25 and of opening ratio (opening height to cavity height) of 1.0, 0.5, and 0.25 were considered in the study. The results are presented in terms of the average Nusselt number for different values of the above experimental parameters. Conclusions are derived for the effect of changing the tilt angle, the aspect ratio, or the opening ratio of the cavity on the average heat transfer coefficient between the cavity and the ambient air. Buoyancy-driven flow in rectangular cavities has been widely investigated by many researchers. This geometry is of special interest in many solar applications such as in solar passive heating, solar concentrators, and solar central receivers. The importance of the geometry extends to other engineering applications such as electronic equipment, fire research, and energy conservation in buildings.« less

  4. Home | Oregon State University Extension Service

    Science.gov Websites

    "How To" Communities OSU Open Campus Oregon's Agricultural Progress Magazine Emerging Issues Oregon's Agricultural Progress cover image Oregon's Agricultural Progress, the research magazine for the Oregon State University Agricultural Experiment Station. Read current OAP issue » Bridges logo image

  5. Recent advancements of wide-angle polarization analysis with 3He neutron spin filters

    NASA Astrophysics Data System (ADS)

    Chen, W. C.; Gentile, T. R.; Ye, Q.; Kirchhoff, A.; Watson, S. M.; Rodriguez-Rivera, J. A.; Qiu, Y.; Broholm, C.

    2016-09-01

    Wide-angle polarization analysis with polarized 3He based neutron spin filters (NSFs) has recently been employed on the Multi-Axis Crystal Spectrometer (MACS) at the National Institute of Standards and Technology Center for Neutron Research (NCNR). Over the past several years, the apparatus has undergone many upgrades to address the fundamental requirements for wide angle polarization analysis using spin exchange optical pumping based 3He NSFs. In this paper, we report substantial improvements in the on-beam-line performance of the apparatus and progress toward routine user capability. We discuss new standard samples used for 3He NSF characterization and the flipping ratio measurement on MACS. We further discuss the management of stray magnetic fields produced by operation of superconducting magnets on the MACS instrument, which can significantly reduce the 3He polarization relaxation time. Finally, we present the results of recent development of horseshoe-shaped wide angle cells.

  6. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yamamoto, Seiichi, E-mail: s-yama@met.nagoya-u.ac.jp; Okumura, Satoshi; Komori, Masataka

    We developed a prototype positron emission tomography (PET) system based on a new concept called Open-close PET, which has two modes: open and close-modes. In the open-mode, the detector ring is separated into two halved rings and subject is imaged with the open space and projection image is formed. In the close-mode, the detector ring is closed to be a regular circular ring, and the subject can be imaged without an open space, and so reconstructed images can be made without artifacts. The block detector of the Open-close PET system consists of two scintillator blocks that use two types ofmore » gadolinium orthosilicate (GSO) scintillators with different decay times, angled optical fiber-based image guides, and a flat panel photomultiplier tube. The GSO pixel size was 1.6 × 2.4 × 7 mm and 8 mm for fast (35 ns) and slow (60 ns) GSOs, respectively. These GSOs were arranged into an 11 × 15 matrix and optically coupled in the depth direction to form a depth-of-interaction detector. The angled optical fiber-based image guides were used to arrange the two scintillator blocks at 22.5° so that they can be arranged in a hexadecagonal shape with eight block detectors to simplify the reconstruction algorithm. The detector ring was divided into two halves to realize the open-mode and set on a mechanical stand with which the distance between the two parts can be manually changed. The spatial resolution in the close-mode was 2.4-mm FWHM, and the sensitivity was 1.7% at the center of the field-of-view. In both the close- and open-modes, we made sagittal (y-z plane) projection images between the two halved detector rings. We obtained reconstructed and projection images of {sup 18}F-NaF rat studies and proton-irradiated phantom images. These results indicate that our developed Open-close PET is useful for some applications such as proton therapy as well as other applications such as molecular imaging.« less

  7. Acromegaly determination using discriminant analysis of the three-dimensional facial classification in Taiwanese.

    PubMed

    Wang, Ming-Hsu; Lin, Jen-Der; Chang, Chen-Nen; Chiou, Wen-Ko

    2017-08-01

    The aim of this study was to assess the size, angles and positional characteristics of facial anthropometry between "acromegalic" patients and control subjects. We also identify possible facial soft tissue measurements for generating discriminant functions toward acromegaly determination in males and females for acromegaly early self-awareness. This is a cross-sectional study. Subjects participating in this study included 70 patients diagnosed with acromegaly (35 females and 35 males) and 140 gender-matched control individuals. Three-dimensional facial images were collected via a camera system. Thirteen landmarks were selected. Eleven measurements from the three categories were selected and applied, including five frontal widths, three lateral depths and three lateral angular measurements. Descriptive analyses were conducted using means and standard deviations for each measurement. Univariate and multivariate discriminant function analyses were applied in order to calculate the accuracy of acromegaly detection. Patients with acromegaly exhibit soft-tissue facial enlargement and hypertrophy. Frontal widths as well as lateral depth and angle of facial changes were evident. The average accuracies of all functions for female patient detection ranged from 80.0-91.40%. The average accuracies of all functions for male patient detection were from 81.0-94.30%. The greatest anomaly observed was evidenced in the lateral angles, with greater enlargement of "nasofrontal" angles for females and greater "mentolabial" angles for males. Additionally, shapes of the lateral angles showed changes. The majority of the facial measurements proved dynamic for acromegaly patients; however, it is problematic to detect the disease with progressive body anthropometric changes. The discriminant functions of detection developed in this study could help patients, their families, medical practitioners and others to identify and track progressive facial change patterns before the possible patients go to the hospital, especially the lateral "angles" which can be calculated by relative point-to-point changes derived from 2D lateral imagery without the 3D anthropometric measurements. This study tries to provide a novel and easy method to detect acromegaly when the patients start to have awareness of abnormal appearance because of facial measurement changes, and it also suggests that undiagnosed patients be urged to go to the hospital as soon as possible for acromegaly early diagnosis.

  8. Simplifying "target" intraocular pressure for different stages of primary open-angle glaucoma and primary angle-closure glaucoma.

    PubMed

    Sihota, Ramanjit; Angmo, Dewang; Ramaswamy, Deepa; Dada, Tanuj

    2018-04-01

    Lowering of intraocular pressure is currently the only therapeutic measure for Glaucoma management. Many longterm, randomized trials have shown the efficacy of lowering IOP, either by a percentage of baseline, or to a specified level. This has lead to the concept of 'Target" IOP, a range of IOP on therapy, that would stabilize the Glaucoma/prevent further visual field loss, without significantly affecting a patient's quality of life. A clinical staging of Glaucoma by optic nerve head evaluation and perimetric parameters, allows a patient's eye to be categorized as having - mild, moderate or severe Glaucomatous damage. An initial attempt should be made to achieve the following IOP range for both POAG or PACG after an iridotomy. In mild glaucoma the initial target IOP range could be kept as 15-17 mmHg, for moderate glaucoma 12-15 mmHg and in the severe stage of glaucomatous damage 10-12 mmHg. Factoring in baseline IOP, age, vascular perfusion parameters, and change on perimetry or imaging during follow up, this range may be reassessed over 6 months to a year. "Target" IOP requires further lowering when the patient continues to progress or develops a systemic disease such as a TIA. Conversely, in the event of a very elderly or sick patient with stable nerve and visual field over time, the target IOP could be raised and medications reduced. An appropriate use of medications/laser/surgery to achieve such a "Target" IOP range in POAG or PACG can maintain visual fields and quality of life, preventing Glaucoma blindness.

  9. Crustal shortening, exhumation, and strain localization in a collisional orogen: The Bajo Pequeño Shear Zone, Sierra de Pie de Palo, Argentina

    NASA Astrophysics Data System (ADS)

    Garber, Joshua M.; Roeske, Sarah M.; Warren, Jessica; Mulcahy, Sean R.; McClelland, William C.; Austin, Lauren J.; Renne, Paul R.; Vujovich, Graciela I.

    2014-07-01

    The Bajo Pequeño Shear Zone (BPSZ) is a lower-crustal shear zone that records shortening and exhumation associated with the establishment of a new plate boundary, and its placement in a regional structural context suggests that local- to regional-scale strain localization occurred with progressive deformation. A kilometer-scale field and analytical cross section through the 80 m thick BPSZ and its adjacent rocks indicates an early Devonian (405-400 Ma) phase of deformation on the western margin of Gondwanan continental crust. The earliest stages of the BPSZ, recorded by metamorphic and microstructural data, involved thrusting of a hotter orthogneiss over a relatively cool pelitic unit, which resulted in footwall garnet growth and reset footwall white mica 40Ar/39Ar ages in proximity to the shear zone. Later stages of BPSZ activity, as recorded by additional microstructures and quartz c-axis opening angles, were characterized by strain localization to the center of the shear zone coincident with cooling and exhumation. These and other data suggest that significant regional tectonism persisted in the Famatinian orogenic system for 60-70 million years after one microplate collision (the Precordillera) but ceased 5-10 million years prior to another (Chilenia). A survey of other synchronous structures shows that strain was accommodated on progressively narrower structures with time, indicating a regional pattern of strain localization and broad thermal relaxation as the Precordillera collision evolved.

  10. Correlation between CHA2DS2-VASc Score and Glaucoma Treatment and Prognosis.

    PubMed

    Pikkel, Yoav Y; Krebs, Daniel; Igal, Vadim; Sharabi-Nov, Adi; Epstein, Irena; Pikkel, Joseph

    2018-01-01

    To find if CHA 2 DS 2 -VASc scale can accurately predict the treatment, prognosis, and outcome for primary open-angle glaucoma (POAG). A survey of 250,000 patient years was taken, using the records of the Ophthalmology Department at Ziv Medical Center. Data was collected regarding the retinal nerve fiber layer (RNFL), visual field (VF), line of treatment (LOT) of glaucoma, and all the data needed to accurately calculate CHA 2 DS 2 -VASc score for each patient. Sixty-seven patients were included in the statistical analysis. The mean age was 72.5 years. The mean CHA 2 DS 2 -VASc score was 3.27 + -1.7. Positive Pearson's correlation coefficients were found for LOT and CHA 2 DS 2 -VASc score, 0.35, and for RNFL grade and CHA2DS2-VASc score, 0.37. The correlation was negative for RNFL width and CHA2DS2-VASc score, -0.35. CHA 2 DS 2 -VASc score was shown to be correlated with glaucoma. This correlation was manifested positively by the LOT needed to stop glaucoma progression, with higher CHA 2 DS 2 -VASc scores correlated with more aggressive treatment. Since glaucoma is a disease with a progressing nature, it is important to treat patients aggressively on one hand, while offering the most benign treatment as possible on the other hand. Modification of the CHA 2 DS 2 -VASc score could achieve an even higher correlation.

  11. Assessment approaches in massive open online courses: Possibilities, challenges and future directions

    NASA Astrophysics Data System (ADS)

    Xiong, Yao; Suen, Hoi K.

    2018-03-01

    The development of massive open online courses (MOOCs) has launched an era of large-scale interactive participation in education. While massive open enrolment and the advances of learning technology are creating exciting potentials for lifelong learning in formal and informal ways, the implementation of efficient and effective assessment is still problematic. To ensure that genuine learning occurs, both assessments for learning (formative assessments), which evaluate students' current progress, and assessments of learning (summative assessments), which record students' cumulative progress, are needed. Providers' more recent shift towards the granting of certificates and digital badges for course accomplishments also indicates the need for proper, secure and accurate assessment results to ensure accountability. This article examines possible assessment approaches that fit open online education from formative and summative assessment perspectives. The authors discuss the importance of, and challenges to, implementing assessments of MOOC learners' progress for both purposes. Various formative and summative assessment approaches are then identified. The authors examine and analyse their respective advantages and disadvantages. They conclude that peer assessment is quite possibly the only universally applicable approach in massive open online education. They discuss the promises, practical and technical challenges, current developments in and recommendations for implementing peer assessment. They also suggest some possible future research directions.

  12. Open access: a closed shop?

    NASA Astrophysics Data System (ADS)

    Bradford, Rick

    2013-01-01

    Your December 2012 issue contains both a short news article on the progress of the open-access movement ("UK open access gains ground", p11) and a lengthy feature about the visionary Irish physicist Edward Hutchinson Synge ("Unknown genius", pp26-29). I find the combination of these articles ironic.

  13. Spatial range of illusory effects in Müller-Lyer figures.

    PubMed

    Predebon, J

    2001-11-01

    The spatial range of the illusory effects in Müller-Lyer (M-L) figures was examined in three experiments. Experiments 1 and 2 assessed the pattern of bisection errors along the shaft of the standard or double-angle (experiment 1) and the single-angle (experiment 2) M-L figures: Subjects bisected the shaft and the resulting two half-segments of the shaft to produce apparently equal quarters, and then each of the quarters to produce eight equal-appearing segments. The bisection judgments of each segment were referenced to the segment's physical midpoints. The expansion or wings-out and the contraction or wings-in figures yielded similar patterns of bisection errors. For the standard M-L figures, there were significant errors in bisecting each half, and each end-quarter, but not the two central quarters of the shaft. For the single-angle M-L figures, there were significant errors in bisecting the length of the shaft, the half-segment, and the quarter, of the shaft adjacent to the vertex but not the second quarter from the vertex nor in dividing the half of the shaft at the open end of the figure into four equal intervals. Experiment 3 assessed the apparent length of the half-segment of the shaft at the open end of the single-angle figures. Length judgments were unaffected by the vertex at the opposite end of the shaft. Taken together, the results indicate that the length distortions in both the standard and single-angle M-L figures are not uniformly distributed along the shaft but rather are confined mainly to the quarters adjacent to the vertices. The present findings imply that theories of the M-L illusion which assume uniform expansion or contraction of the shafts are incomplete.

  14. Medial meniscus posterior root tear induces pathological posterior extrusion of the meniscus in the knee-flexed position: An open magnetic resonance imaging analysis.

    PubMed

    Masuda, S; Furumatsu, T; Okazaki, Y; Kodama, Y; Hino, T; Kamatsuki, Y; Miyazawa, S; Ozaki, T

    2018-04-10

    A medial meniscus posterior root tear (MMPRT) is defined as an injury to the posterior meniscal insertion on the tibia. In MMPRT, the medial meniscus (MM) hoop function is damaged, and the MM undergoes a medial extrusion into the interior from the superior articular surface of the tibia. However, the details of MM position and movement during knee joint movement are unclear in MMPRT cases. The present study aims to evaluate MM position and movement via magnetic resonance imaging (MRI) examination of the MM posterior extrusion (MMPE) at knee flexion angles of 10° and 90°. We hypothesized that, during knee flexion, the MM will shift to the posterior and the posterior extrusion will increase compared to that when the knee is extended. Twenty-four patients were diagnosed with symptomatic MMPRT on open MRI examination. Preoperative MMPE, anteroposterior interval (API) of the MM, and MM medial extrusion (MMME) at knee flexion angles of 10° and 90° were measured. For patients with MMPRT, the MMPE increased from -4.77±1.43mm to 3.79±1.17mm (p<0.001) when the knee flexion angle increased from 10° to 90°. Further, flexing the knee from 10° to 90° decreased the API of the MM from 20.19±4.22mm to 16.41±5.14mm (p<0.001). MMME showed no significant change between knee flexion angles of 10° and 90°. This study demonstrated that, in cases of MMPRT, the MMPE clearly increases when the knee is flexed to 90°, while MMME does not change. Our results suggest that open MRI examination can be used to evaluate the dynamic position of the posterior MM by scanning the knee as it flexes to 90°. IV: retrospective cohort study. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  15. Geometrically distributed one-dimensional photonic crystals for light-reflection in all angles.

    PubMed

    Alagappan, G; Wu, P

    2009-07-06

    We demonstrate that a series of one-dimensional photonic crystals made of any dielectric materials, with the periods are distributed in a geometrical progression of a common ratio, r < rc (theta,P), where rc is a structural parameter that depends on the angle of incidence, theta, and polarization, P, is capable of blocking light of any spectral range. If an omni-directional reflection is desired for all polarizations and for all incident angles smaller than thetao, then r < rc (theta(o),p), where p is the polarization with the electric field parallel to the plane of incidence. We present simple and formula like expressions for rc, width of the bandgap, and minimum number of photonic crystals to achieve a perfect light reflection.

  16. Initial experience with purely laparoscopic living-donor right hepatectomy.

    PubMed

    Hong, S K; Lee, K W; Choi, Y; Kim, H S; Ahn, S W; Yoon, K C; Kim, H; Yi, N J; Suh, K S

    2018-05-01

    There may be concerns about purely laparoscopic donor right hepatectomy (PLDRH) compared with open donor right hepatectomy, especially when performed by surgeons accustomed to open surgery. This study aimed to describe technical tips and pitfalls in PLDRH. Data from donors who underwent PLDRH at Seoul National University Hospital between December 2015 and July 2017 were analysed retrospectively. Endpoints analysed included intraoperative events and postoperative complications. All operations were performed by a single surgeon with considerable experience in open living donor hepatectomy. A total of 26 donors underwent purely laparoscopic right hepatectomy in the study interval. No donor required transfusion during surgery, whereas two underwent reoperation. In two donors, the dissection plane at the right upper deep portion of the midplane was not correct. One donor experienced portal vein injury during caudate lobe transection, and one developed remnant left hepatic duct stenosis. One donor experienced remnant portal vein angulation owing to a different approach angle, and one experienced arterial damage associated with the use of a laparoscopic energy device. One donor had postoperative bleeding due to masking of potential bleeding foci owing to intra-abdominal pressure during laparoscopy. Two donors experienced right liver surface damage caused by a xiphoid trocar. Purely laparoscopic donor hepatectomy differs from open donor hepatectomy in terms of angle and caudal view. Therefore, surgeons experienced in open donor hepatectomy must gain adequate experience in laparoscopic liver surgery and make adjustments when performing PLDRH. © 2018 BJS Society Ltd Published by John Wiley & Sons Ltd.

  17. Generalized Brewster effect in dielectric metasurfaces

    PubMed Central

    Paniagua-Domínguez, Ramón; Yu, Ye Feng; Miroshnichenko, Andrey E.; Krivitsky, Leonid A.; Fu, Yuan Hsing; Valuckas, Vytautas; Gonzaga, Leonard; Toh, Yeow Teck; Kay, Anthony Yew Seng; Luk'yanchuk, Boris; Kuznetsov, Arseniy I.

    2016-01-01

    Polarization is a key property defining the state of light. It was discovered by Brewster, while studying light reflected from materials at different angles. This led to the first polarizers, based on Brewster's effect. Now, one of the trends in photonics is the study of miniaturized devices exhibiting similar, or improved, functionalities compared with bulk optical elements. In this work, it is theoretically predicted that a properly designed all-dielectric metasurface exhibits a generalized Brewster's effect potentially for any angle, wavelength and polarization of choice. The effect is experimentally demonstrated for an array of silicon nanodisks at visible wavelengths. The underlying physics is related to the suppressed scattering at certain angles due to the interference between the electric and magnetic dipole resonances excited in the nanoparticles. These findings open doors for Brewster phenomenon to new applications in photonics, which are not bonded to a specific polarization or angle of incidence. PMID:26783075

  18. Increasing light coupling in a photovoltaic film by tuning nanoparticle shape with substrate surface energy

    NASA Astrophysics Data System (ADS)

    Kataria, Devika; Krishnamoorthy, Kothandam; Iyer, S. Sundar Kumar

    2017-08-01

    Tuning metal nanoparticle (MNP) contact angle on the surface it is formed can help maximise the useful optical coupling in photovoltaic films by localized surface plasmon (LSP) resonance—opening up the possibility of building improved photovoltaic cells. In this work experimental demonstration of optical absorption increase in copper phthalocyanine (CuPc) films by tuning silver MNP shape by changing its contact angles with substrate has been reported. Thin films of poly3,4 ethylenedioxythiophene: sodium dodecycl sulphate (PEDOT:SDS) with different surface energies were formed on indium tin oxide (ITO) coated glass by electro-deposition. Silver MNPs thermally evaporated directly on ozonised ITO as well as on the PEDOT:SDS films showed contact angles ranging from 60° to 125°. The CuPc layer was deposited on top of the MNPs. For the samples studied, best optical absorption in the CuPc layer was for a contact angle of 110°.

  19. Optimal operation of turbo blowers serially connected using inlet vanes

    NASA Astrophysics Data System (ADS)

    Jang, Choon-Man

    2011-03-01

    Optimal operation of the turbo blowers having an inlet vane has been studied to understand the blowers' operating performance. To analyze three-dimensional flow field in the turbo blowers serially connected, general analysis code, CFX, is introduced in the present work. SST turbulence model is employed to estimate the eddy viscosity. Throughout the numerical analysis, it is found that the flow rates of the turbo blowers can be controlled at the vane angle between 90 (full open condition) degrees and 60 degrees effectively, because pressure loss rapidly increases below 60 degree of a vane angle. Efficiency also has almost the same values from 90 degrees to 60 degrees of a vane angle. It is noted that the distorted inlet velocity generated in the small vane angle makes performance deterioration of the turbo blowers due to the local leading edge separation and the following non-uniform blade loading.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    García-Cervantes, H.; Sotolongo-Costa, O.; Gaggero-Sager, L. M.

    Graphene Superlattices (GSs) have attracted a lot of attention due to its peculiar properties as well as its possible technological implications. Among these characteristics we can mention: the extra Dirac points in the dispersion relation and the highly anisotropic propagation of the charge carriers. However, despite the intense research that is carried out in GSs, so far there is no report about the angular dependence of the Transmission Gap (TG) in GSs. Here, we report the dependence of TG as a function of the angle of the incident Dirac electrons in a rather simple Electrostatic GS (EGS). Our results showmore » that the angular dependence of the TG is intricate, since for moderated angles the dependence is parabolic, while for large angles an exponential dependence is registered. We also find that the TG can be modulated from meV to eV, by changing the structural parameters of the GS. These characteristics open the possibility for an angle-dependent bandgap engineering in graphene.« less

  1. 75 FR 69737 - Qualification of Drivers; Exemption Applications; Vision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ... moving violations in a CMV. Michael E. Herrera, Jr., Mr. Herrera, 53, has had primary open angle glaucoma... opinion. Mr. Herrera has sufficient vision to drive a commercial vehicle. Mr. Herrera reported that he has...

  2. Bend losses in rectangular culverts.

    DOT National Transportation Integrated Search

    2008-09-01

    This study investigated bend losses for open channel flow in rectangular channels or culverts. Laboratory experiments were performed for sub-critical flow in rectangular channels with abrupt bends. Bend angles of approximately 30, 45, 60, 75 and 90 d...

  3. Laser beam guard clamps

    DOEpatents

    Dickson, Richard K.

    2010-09-07

    A quick insert and release laser beam guard panel clamping apparatus having a base plate mountable on an optical table, a first jaw affixed to the base plate, and a spring-loaded second jaw slidably carried by the base plate to exert a clamping force. The first and second jaws each having a face acutely angled relative to the other face to form a V-shaped, open channel mouth, which enables wedge-action jaw separation by and subsequent clamping of a laser beam guard panel inserted through the open channel mouth. Preferably, the clamping apparatus also includes a support structure having an open slot aperture which is positioned over and parallel with the open channel mouth.

  4. Micromechanical torsional digital-to-analog converter for open-loop angular positioning applications

    NASA Astrophysics Data System (ADS)

    Zhou, Guangya; Tay, Francis E. H.; Chau, Fook Siong; Zhao, Yi; Logeeswaran, VJ

    2004-05-01

    This paper reports a novel micromechanical torsional digital-to-analog converter (MTDAC), operated in open-loop with digitally controlled precise multi-level tilt angles. The MTDAC mechanism presented is analogous to that of an electrical binary-weighted-input digital-to-analog converter (DAC). It consists of a rigid tunable platform, an array of torsional microactuators, each operating in a two-state (on/off) mode, and a set of connection beams with binary-weighted torsional stiffnesses that connect the actuators to the platform. The feasibility of the proposed MTDAC mechanism was verified numerically by finite element simulations and experimentally with a commercial optical phase-shifting interferometric system. A prototype 2-bit MTDAC was implemented using the poly-MUMPS process achieving a full-scale output tilt angle of 1.92° with a rotation step of 0.64°. This mechanism can be configured for many promising applications, particularly in beam steering-based OXC switches.

  5. Multifocal visual evoked potentials for early glaucoma detection.

    PubMed

    Weizer, Jennifer S; Musch, David C; Niziol, Leslie M; Khan, Naheed W

    2012-07-01

    To compare multifocal visual evoked potentials (mfVEP) with other detection methods in early open-angle glaucoma. Ten patients with suspected glaucoma and 5 with early open-angle glaucoma underwent mfVEP, standard automated perimetry (SAP), short-wave automated perimetry, frequency-doubling technology perimetry, and nerve fiber layer optical coherence tomography. Nineteen healthy control subjects underwent mfVEP and SAP for comparison. Comparisons between groups involving continuous variables were made using independent t tests; for categorical variables, Fisher's exact test was used. Monocular mfVEP cluster defects were associated with an increased SAP pattern standard deviation (P = .0195). Visual fields that showed interocular mfVEP cluster defects were more likely to also show superior quadrant nerve fiber layer thinning by OCT (P = .0152). Multifocal visual evoked potential cluster defects are associated with a functional and an anatomic measure that both relate to glaucomatous optic neuropathy. Copyright 2012, SLACK Incorporated.

  6. EX-PRESS Glaucoma Filtration Device: efficacy, safety, and predictability

    PubMed Central

    Chan, Jessica E; Netland, Peter A

    2015-01-01

    Trabeculectomy has been the traditional primary surgical therapy for open-angle glaucoma. While trabeculectomy is effective in lowering intraocular pressure, complications associated with the procedure have motivated the development of alternative techniques and devices, including the EX-PRESS Glaucoma Filtration Device. This review describes the efficacy, safety, complication rates, and potential advantages and disadvantages of the EX-PRESS Glaucoma Filtration Device. EX-PRESS implantation is technically simpler compared with that of trabeculectomy, with fewer surgical steps. Vision recovery has been more rapid after EX-PRESS implantation compared with trabeculectomy. Intraocular pressure variation is lower during the early postoperative period, indicating a more predictable procedure. While efficacy of the EX-PRESS implant has been comparable to trabeculectomy, postoperative complications appear less common after EX-PRESS implantation compared with trabeculectomy. The EX-PRESS Glaucoma Filtration Device appears to be safe and effective in the surgical management of open-angle glaucoma. PMID:26366105

  7. Common variants near CAV1 and CAV2 are associated with primary open-angle glaucoma

    PubMed Central

    Thorleifsson, Gudmar; Walters, G Bragi; Hewitt, Alex W; Masson, Gisli; Helgason, Agnar; DeWan, Andrew; Sigurdsson, Asgeir; Jonasdottir, Adalbjorg; Gudjonsson, Sigurjon A; Magnusson, Kristinn P; Stefansson, Hreinn; Lam, Dennis S C; Tam, Pancy O S; Gudmundsdottir, Gudrun J; Southgate, Laura; Burdon, Kathryn P; Gottfredsdottir, Maria Soffia; Aldred, Micheala A; Mitchell, Paul; St Clair, David; Collier, David A; Tang, Nelson; Sveinsson, Orn; Macgregor, Stuart; Martin, Nicholas G; Cree, Angela J; Gibson, Jane; MacLeod, Alex; Jacob, Aby; Ennis, Sarah; Young, Terri L; Chan, Juliana C N; Karwatowski, Wojciech S S; Hammond, Christopher J; Thordarson, Kristjan; Zhang, Mingzhi; Wadelius, Claes; Lotery, Andrew J; Trembath, Richard C; Pang, Chi Pui; Hoh, Josephine; Craig, Jamie E; Kong, Augustine; Mackey, David A; Jonasson, Fridbert; Thorsteinsdottir, Unnur; Stefansson, Kari

    2011-01-01

    We conducted a genome-wide association study for primary open-angle glaucoma (POAG) in 1,263 affected individuals (cases) and 34,877 controls from Iceland. We identified a common sequence variant at 7q31 (rs4236601[A], odds ratio (OR) = 1.36, P = 5.0 × 10-10). We then replicated the association in sample sets of 2,175 POAG cases and 2,064 controls from Sweden, the UK and Australia (combined OR = 1.18, P = 0.0015) and in 299 POAG cases and 580 unaffected controls from Hong Kong and Shantou, China (combined OR = 5.42, P = 0.0021). The risk variant identified here is located close to CAV1 and CAV2, both of which are expressed in the trabecular meshwork and retinal ganglion cells that are involved in the pathogenesis of POAG. PMID:20835238

  8. Empowering Learners with Mobile Open-Access Learning Initiatives

    ERIC Educational Resources Information Center

    Mills, Michael, Ed.; Wake, Donna, Ed.

    2017-01-01

    Education has been progressing at a rapid pace ever since educators have been able to harness the power of mobile technology. Open-access learning techniques provide more students with the opportunity to engage in educational opportunities that may have been previously restricted. "Empowering Learners with Mobile Open-Access Learning…

  9. Open Education: Promise and Problems. Fastback Series, No. 3.

    ERIC Educational Resources Information Center

    Perrone, Vito

    The term "open education" is used to designate the curriculum and instruction methods associated with an open plan school -- one without interior walls. Such a program consists of more advanced children assisting those less advanced, independent study, children progressing at their own rate, extensive use of the outdoor environment,…

  10. Open Educational Resources: Staff Attitudes and Awareness

    ERIC Educational Resources Information Center

    Rolfe, Vivien

    2012-01-01

    Attitudes are changing in education globally to promote the open sharing of educational courses and resources. The aim of this study was to explore staff awareness and attitudes towards "open educational resources" (OER) as a benchmark for monitoring future progress. Faculty staff (n = 6) were invited to participate in semi-structured…

  11. Cross-coupling between accommodation and convergence is optimized for a broad range of directions and distances of gaze.

    PubMed

    Nguyen, Dorothy; Vedamurthy, Indu; Schor, Clifton

    2008-03-01

    Accommodation and convergence systems are cross-coupled so that stimulation of one system produces responses by both systems. Ideally, the cross-coupled responses of accommodation and convergence match their respective stimuli. When expressed in diopters and meter angles, respectively, stimuli for accommodation and convergence are equal in the mid-sagittal plane when viewed with symmetrical convergence, where historically, the gains of the cross coupling (AC/A and CA/C ratios) have been quantified. However, targets at non-zero azimuth angles, when viewed with asymmetric convergence, present unequal stimuli for accommodation and convergence. Are the cross-links between the two systems calibrated to compensate for stimulus mismatches that increase with gaze-azimuth? We measured the response AC/A and stimulus CA/C ratios at zero azimuth, 17.5 and 30 deg of rightward gaze eccentricities with a Badal Optometer and Wheatstone-mirror haploscope. AC/A ratios were measured under open-loop convergence conditions along the iso-accommodation circle (locus of points that stimulate approximately equal amounts of accommodation to the two eyes at all azimuth angles). CA/C ratios were measured under open-loop accommodation conditions along the iso-vergence circle (locus of points that stimulate constant convergence at all azimuth angles). Our results show that the gain of accommodative-convergence (AC/A ratio) decreased and the bias of convergence-accommodation increased at the 30 deg gaze eccentricity. These changes are in directions that compensate for stimulus mismatches caused by spatial-viewing geometry during asymmetric convergence.

  12. 3D DEM analyses of the 1963 Vajont rock slide

    NASA Astrophysics Data System (ADS)

    Boon, Chia Weng; Houlsby, Guy; Utili, Stefano

    2013-04-01

    The 1963 Vajont rock slide has been modelled using the distinct element method (DEM). The open-source DEM code, YADE (Kozicki & Donzé, 2008), was used together with the contact detection algorithm proposed by Boon et al. (2012). The critical sliding friction angle at the slide surface was sought using a strength reduction approach. A shear-softening contact model was used to model the shear resistance of the clayey layer at the slide surface. The results suggest that the critical sliding friction angle can be conservative if stability analyses are calculated based on the peak friction angles. The water table was assumed to be horizontal and the pore pressure at the clay layer was assumed to be hydrostatic. The influence of reservoir filling was marginal, increasing the sliding friction angle by only 1.6˚. The results of the DEM calculations were found to be sensitive to the orientations of the bedding planes and cross-joints. Finally, the failure mechanism was investigated and arching was found to be present at the bend of the chair-shaped slope. References Boon C.W., Houlsby G.T., Utili S. (2012). A new algorithm for contact detection between convex polygonal and polyhedral particles in the discrete element method. Computers and Geotechnics, vol 44, 73-82, doi.org/10.1016/j.compgeo.2012.03.012. Kozicki, J., & Donzé, F. V. (2008). A new open-source software developed for numerical simulations using discrete modeling methods. Computer Methods in Applied Mechanics and Engineering, 197(49-50), 4429-4443.

  13. Hyperkyphosis, Kyphosis Progression, and Risk of Non-Spine Fractures in Older Community Dwelling Women: The Study of Osteoporotic Fractures (SOF)

    PubMed Central

    Kado, Deborah M.; Miller-Martinez, Dana; Lui, Li-Yung; Cawthon, Peggy; Katzman, Wendy B.; Hillier, Teresa A.; Fink, Howard A.; Ensrud, Kristine E.

    2014-01-01

    While accentuated kyphosis is associated with osteoporosis, it is unknown whether it increases risk of future fractures, independent of bone mineral density (BMD) and vertebral fractures. We examined the associations of baseline Cobb angle kyphosis and 15 year change in kyphosis with incident non-spine fractures using data from the Study of Osteoporotic Fractures. A total of 994 predominantly white women, aged 65 or older, were randomly sampled from 9,704 original participants to have repeated Cobb angle measurements of kyphosis measured from lateral spine radiographs at baseline and an average of 15 years later. Non-spine fractures, confirmed by radiographic report, were assessed every four months for up to 21.3 years. Compared with women in the lower three quartiles of kyphosis, women with kyphosis greater than 53 degrees (top quartile) had a 50% increased risk of non-spine fracture (95% CI, 1.10 –2.06 after adjusting for BMD, prevalent vertebral fractures, prior history of fractures, and other fracture risk factors. Cobb angle kyphosis progressed an average of 7 degrees (SD = 6.8) over 15 years. Per 1 SD increase in kyphosis change, there was a multivariable adjusted 28% increased risk of fracture (95% CI, 1.06 – 1.55) that was attenuated by further adjustment for baseline BMD (HR per SD increase in kyphosis change, 1.19; 95% CI 0.99 –1.44). Greater kyphosis is associated with an elevated non-spine fracture risk independent of traditional fracture risk factors in older women. Furthermore, worsening kyphosis is also associated with increased fracture risk that is partially mediated by low baseline BMD that itself is a risk factor for kyphosis progression. These results suggest that randomized controlled fracture intervention trials should consider implementing kyphosis measures to: 1) further study kyphosis and kyphosis change as an additional fracture risk factor; and 2) test whether therapies may improve or delay its progression. PMID:24715607

  14. Hyperkyphosis, kyphosis progression, and risk of non-spine fractures in older community dwelling women: the study of osteoporotic fractures (SOF).

    PubMed

    Kado, Deborah M; Miller-Martinez, Dana; Lui, Li-Yung; Cawthon, Peggy; Katzman, Wendy B; Hillier, Teresa A; Fink, Howard A; Ensrud, Kristine E

    2014-10-01

    While accentuated kyphosis is associated with osteoporosis, it is unknown whether it increases risk of future fractures, independent of bone mineral density (BMD) and vertebral fractures. We examined the associations of baseline Cobb angle kyphosis and 15 year change in kyphosis with incident non-spine fractures using data from the Study of Osteoporotic Fractures. A total of 994 predominantly white women, aged 65 or older, were randomly sampled from 9704 original participants to have repeated Cobb angle measurements of kyphosis measured from lateral spine radiographs at baseline and an average of 15 years later. Non-spine fractures, confirmed by radiographic report, were assessed every 4 months for up to 21.3 years. Compared with women in the lower three quartiles of kyphosis, women with kyphosis greater than 53° (top quartile) had a 50% increased risk of non-spine fracture (95% CI, 1.10-2.06 after adjusting for BMD, prevalent vertebral fractures, prior history of fractures, and other fracture risk factors. Cobb angle kyphosis progressed an average of 7° (SD = 6.8) over 15 years. Per 1 SD increase in kyphosis change, there was a multivariable adjusted 28% increased risk of fracture (95% CI, 1.06-1.55) that was attenuated by further adjustment for baseline BMD (HR per SD increase in kyphosis change, 1.19; 95% CI 0.99-1.44). Greater kyphosis is associated with an elevated non-spine fracture risk independent of traditional fracture risk factors in older women. Furthermore, worsening kyphosis is also associated with increased fracture risk that is partially mediated by low baseline BMD that itself is a risk factor for kyphosis progression. These results suggest that randomized controlled fracture intervention trials should consider implementing kyphosis measures to the following: (1) further study kyphosis and kyphosis change as an additional fracture risk factor; and (2) test whether therapies may improve or delay its progression. © 2014 American Society for Bone and Mineral Research.

  15. Survey views of the Mir space station

    NASA Image and Video Library

    1997-10-20

    STS086-720-007 (25 Sept.-6 Oct. 1997) --- A 70mm view of Russia’s Mir Space Station’s Spektr Module shows the backside of a solar array panel and damage incurred by the impact of a Russian unmanned Progress re-supply ship which collided with the space station on June 25, 1997, causing Spektr to depressurize. A radiator, which also was struck by the Progress, is out of view from this angle. Photo credit: NASA

  16. Slow relaxation in weakly open rational polygons.

    PubMed

    Kokshenev, Valery B; Vicentini, Eduardo

    2003-07-01

    The interplay between the regular (piecewise-linear) and irregular (vertex-angle) boundary effects in nonintegrable rational polygonal billiards (of m equal sides) is discussed. Decay dynamics in polygons (of perimeter P(m) and small opening Delta) is analyzed through the late-time survival probability S(m) approximately equal t(-delta). Two distinct slow relaxation channels are established. The primary universal channel exhibits relaxation of regular sliding orbits, with delta=1. The secondary channel is given by delta>1 and becomes open when m>P(m)/Delta. It originates from vertex order-disorder dual effects and is due to relaxation of chaoticlike excitations.

  17. Surgical Orthodontic Treatment for Open Bite in Noonan Syndrome Patient: A Case Report.

    PubMed

    Kawakami, Masayoshi; Yamamoto, Kazuhiko; Shimomura, Tadahiro; Kirita, Tadaaki

    2016-03-01

    Noonan syndrome, characterized by short stature, facial anomalies, and congenital heart defects, may also be associated with hematopoietic disorders. Craniofacial anomalies in affected patients include hypertelorism and severe open bite associated with masticatory dysfunction. We treated a Noonan syndrome patient with a skeletal open bite. Surgical orthodontic treatment including two-jaw surgery established a good occlusal relationship after correction of severe anemia. Both upper and lower incisors were moved to upright positions, while clockwise rotation of the palatal plane and decreased mandibular plane angle were accomplished. Lower masticatory activity may affect posttreatment occlusion in such cases.

  18. Acoustic Shielding for a Model Scale Counter-rotation Open Rotor

    NASA Technical Reports Server (NTRS)

    Stephens, David B.; Edmane, Envia

    2012-01-01

    The noise shielding benefit of installing an open rotor above a simplified wing or tail is explored experimentally. The test results provide both a benchmark data set for validating shielding prediction tools and an opportunity for a system level evaluation of the noise reduction potential of propulsion noise shielding by an airframe component. A short barrier near the open rotor was found to provide up to 8.5 dB of attenuation at some directivity angles, with tonal sound particularly well shielded. Predictions from two simple shielding theories were found to overestimate the shielding benefit.

  19. Method of sealing

    DOEpatents

    Groh, Edward F.; Cassidy, Dale A.

    1978-01-01

    A thermocouple lead or other small diameter wire, cable or tube is passed through a thin material such as sheet metal and sealed thereinto by drawing complementary longitudinally angled, laterally rounded grooves terminating at their base ends in a common plane in both sides of the thin material with shearing occuring at the deep end faces thereof to form a rounded opening in the thin material substantially perpendicular to the plane of the thin material, passing a thermocouple lead or similar object through the opening so formed and sealing the opening with a sealant which simultaneously bonds the lead to the thin material.

  20. Modeling the effect of preexisting joints on normal fault geometries using a brittle and cohesive material

    NASA Astrophysics Data System (ADS)

    Kettermann, M.; van Gent, H. W.; Urai, J. L.

    2012-04-01

    Brittle rocks, such as for example those hosting many carbonate or sandstone reservoirs, are often affected by different kinds of fractures that influence each other. Understanding the effects of these interactions on fault geometries and the formation of cavities and potential fluid pathways might be useful for reservoir quality prediction and production. Analogue modeling has proven to be a useful tool to study faulting processes, although usually the used materials do not provide cohesion and tensile strength, which are essential to create open fractures. Therefore, very fine-grained, cohesive, hemihydrate powder was used for our experiments. The mechanical properties of the material are scaling well for natural prototypes. Due to the fine grain size structures are preserved in in great detail. The used deformation box allows the formation of a half-graben and has initial dimensions of 30 cm width, 28 cm length and 20 cm height. The maximum dip-slip along the 60° dipping predefined basement fault is 4.5 cm and was fully used in all experiments. To setup open joints prior to faulting, sheets of paper placed vertically within the box to a depth of about 5 cm from top. The powder was then sieved into the box, embedding the paper almost entirely. Finally strings were used to remove the paper carefully, leaving open voids. Using this method allows the creation of cohesionless open joints while ensuring a minimum impact on the sensitive surrounding material. The presented series of experiments aims to investigate the effect of different angles between the strike of a rigid basement fault and a distinct joint set. All experiments were performed with a joint spacing of 2.5 cm and the fault-joint angles incrementally covered 0°, 4°, 8°, 12°, 16°, 20° and 25°. During the deformation time lapse photography from the top and side captured every structural change and provided data for post-processing analysis using particle imaging velocimetry (PIV). Additionally, stereo-photography at the final stage of deformation enabled the creation of 3D models to preserve basic geometric information. The models showed that at the surface the deformation localized always along preexisting joints, even when they strike at an angle to the basement-fault. In most cases faults intersect precisely at the maximum depth of the joints. With increasing fault-joint angle the deformation occurred distributed over several joints by forming stepovers with fractures oriented normal to the strike of the joints. No fractures were observed parallel to the basement fault. At low angles stepovers coincided with wedge-shaped structures between two joints that remain higher than the surrounding joint-fault intersection. The wide opening gap along the main fault allowed detailed observations of the fault planes at depth, which revealed (1) changing dips according to joint-fault angles, (2) slickenlines, (3) superimposed steepening fault-planes, causing sharp sawtooth-shaped structures. Comparison to a field analogue at Canyonlands National Park, Utah/USA showed similar structures and features such as vertical fault escarpments at the surface coinciding with joint-surfaces. In the field and in the models stepovers were observed as well as conjugate faulting and incremental fault-steepening.

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